Sample records for mfrsr multifilter rotating

  1. Multifilter Rotating Shadowband Radiometer (MFRSR) Handbook

    SciTech Connect (OSTI)

    Hodges, GB; Michalsky, JJ

    2011-02-07T23:59:59.000Z

    The visible Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at six narrowband channels and one open, or broadband, channel (Harrison et al. 1994). Direct irradiance is not a primary measurement, but is calculated using the diffuse and global measurements. To collect one data record, the MFRSR takes measurements at four different shadowband positions. The first measurement is taken with the shadowband in the nadir (home) position. The next three measurements are, in order, the first side-band, sun-blocked, and second side-band. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. The nominal wavelengths of the narrowband channels are 415, 500, 615, 673, 870, and 940 nm. From such measurements, one may infer the atmosphere's aerosol optical depth at each wavelength. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Harrison and Michalsky 1994) and other atmospheric constituents.

  2. ARM Multi-Filter Rotating Shadowband Radiometer (MFRSR): irradiances

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Hodges, Gary

    The multifilter rotating shadowband radiometer (MFRSR) takes spectral measurements of direct normal, diffuse horizontal and total horizontal solar irradiances. These measurements are at nominal wavelengths of 415, 500, 615, 673, 870, and 940 nm. The measurements are made at a user-specified time interval, usually about one minute or less. The sampling rate for the Atmospheric Radiation Measurement (ARM) Climate Research Facility MFRSRs is 20 seconds. From such measurements, one may infer the atmosphere's optical depth at the wavelengths mentioned above. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Michalsky et al. 1994) and other atmospheric constituents. A silicon detector is also part of the MFRSR. This detector provides a measure of the broadband direct normal, diffuse horizontal and total horizontal solar irradiances. A MFRSR head that is mounted to look vertically downward can measure upwelling spectral irradiances. In the ARM system, this instrument is called a multifilter radiometer (MFR). At the Southern Great Plains (SGP) there are two MFRs; one mounted at the 10-m height and the other at 25 m. At the North Slope of Alaska (NSA) sites, the MFRs are mounted at 10 m. MFRSR heads are also used to measure normal incidence radiation by mounting on a solar tracking device. These are referred to as normal incidence multi-filter radiometers (NIMFRs) and are located at the SGP and NSA sites. Another specialized use for the MFRSR is the narrow field of view (NFOV) instrument located at SGP. The NFOV is a ground-based radiometer (MFRSR head) that looks straight up.

  3. The multi-filter rotating shadowband radiometer (MFRSR) - precision infrared radiometer (PIR) platform in Fairbanks: Scientific objectives

    SciTech Connect (OSTI)

    Stamnes, K.; Leontieva, E. [Univ. of Alaska, Fairbanks (United States)

    1996-04-01T23:59:59.000Z

    The multi-filter rotating shadowband radiometer (MFRSR) and precision infrared radiometer (PIR) have been employed at the Geophysical Institute in Fairbanks to check their performance under arctic conditions. Drawing on the experience of the previous measurements in the Arctic, the PIR was equipped with a ventilator to prevent frost and moisture build-up. We adopted the Solar Infrared Observing Sytem (SIROS) concept from the Southern Great Plains Cloud and Radiation Testbed (CART) to allow implementation of the same data processing software for a set of radiation and meteorological instruments. To validate the level of performance of the whole SIROS prior to its incorporation into the North Slope of Alaska (NSA) Cloud and Radiation Testbed Site instrumental suite for flux radiatin measurements, the comparison between measurements and model predictions will be undertaken to assess the MFRSR-PIR Arctic data quality.

  4. Multi-Filter Rotating Shadowband Radiometers Mentor Report and Baseline Surface Radiation Network Submission Status

    SciTech Connect (OSTI)

    Hodges, G.

    2005-03-18T23:59:59.000Z

    There are currently twenty-four Multi-Filter Rotating Shadowband Radiometers (MFRSR) operating within Atmospheric Radiation Measurement (ARM). Eighteen are located within the Southern Great Plains (SGP) region, there is one at each of the North Slope of Alaska (NSA) and Tropical Western Pacific (TWP) sites, and one is part of the instrumentation of the ARM Mobile Facility. At this time there are four sites, all extended facilities within the SGP, that are equipped for a MFRSR but do not have one due to instrument failure and a lack of spare instruments. In addition to the MFRSRs, there are three other MFRSR derived instruments that ARM operates. They are the Multi-Filter Radiometer (MFR), the Normal Incidence Multi-Filter Radiometer (NIMFR) and the Narrow Field of View (NFOV) radiometer. All are essentially just the head of a MFRSR used in innovative ways. The MFR is mounted on a tower and pointed at the surface. At the SGP Central Facility there is one at ten meters and one at twenty-five meters. The NSA has a MFR at each station, both at the ten meter level. ARM operates three NIMFRs; one is at the SGP Central Facility and one at each of the NSA stations. There are two NFOVs, both at the SGP Central Facility. One is a single channel (870) and the other utilizes two channels (673 and 870).

  5. Aerosol Retrievals from ARM SGP MFRSR Data

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Alexandrov, Mikhail

    The Multi-Filter Rotating Shadowband Radiometer (MFRSR) makes precise simultaneous measurements of the solar direct normal and diffuse horizontal irradiances at six wavelengths (nominally 415, 500, 615, 673, 870, and 940 nm) at short intervals (20 sec for ARM instruments) throughout the day. Time series of spectral optical depth are derived from these measurements. Besides water vapor at 940 nm, the other gaseous absorbers within the MFRSR channels are NO2 (at 415, 500, and 615 nm) and ozone (at 500, 615, and 670 nm). Aerosols and Rayleigh scattering contribute atmospheric extinction in all MFRSR channels. Our recently updated MFRSR data analysis algorithm allows us to partition the spectral aerosol optical depth into fine and coarse modes and to retrieve the fine mode effective radius. In this approach we rely on climatological amounts of NO2 from SCIAMACHY satellite retrievals and use daily ozone columns from TOMS.

  6. Rotating Shadowband Spectroradiometer (RSS) Handbook

    SciTech Connect (OSTI)

    Kiedron, P; Schlemmer, J; Klassen, M

    2005-01-01T23:59:59.000Z

    The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range.

  7. Aerosol Single-Scattering Albedo and Asymmetry Parameter from MFRSR Observations during the ARM Aerosol IOP 2003

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Flynn, Connor J.; Ackerman, Thomas P.; Barnard, James C.

    2007-06-15T23:59:59.000Z

    Multi-filter Rotating Shadowband Radiometers (MFRSRs) provide routine measurements of the aerosol optical depth ( << OLE Object: Microsoft Equation 3.0 >> ) at six wavelengths (0.415, 0.5, 0.615, 0.673, 0.870 and 0.94  << OLE Object: Picture (Metafile) >> ). The single-scattering albedo ( << OLE Object: Microsoft Equation 3.0 >> ) is typically estimated from the MFRSR measurements by assuming the asymmetry parameter ( << OLE Object: Microsoft Equation 3.0 >> ). In most instances, however, it is not easy to set an appropriate value of << OLE Object: Microsoft Equation 3.0 >> due to its strong temporal and spatial variability. Here, we introduce and validate an updated version of our retrieval technique that allows one to estimate simultaneously << OLE Object: Microsoft Equation 3.0 >> and << OLE Object: Microsoft Equation 3.0 >> for different types of aerosol. We use the aerosol and radiative properties obtained during the Atmospheric Science Program (ARM) Aerosol Intensive Operational Period (IOP) to validate our retrieval in two ways. First, the MFRSR-retrieved optical properties are compared with those obtained from independent surface, Aerosol Robotic Network (AERONET) and aircraft measurements. The MFRSR-retrieved optical properties are in reasonable agreement with these independent measurements. Second, we perform radiative closure experiments using the MFRSR-retrieved optical properties. The calculated broadband values of the direct and diffuse fluxes are comparable (~ 5 << OLE Object: Microsoft Equation 3.0 >> ) to those obtained from measurements.

  8. Retrieval of Optical And Size Parameters of Aerosols Utilizing a Multi-Filter Rotating Shadowband Radiometer and Inter-Comparison with CIMEL Sun Photometer and

    E-Print Network [OSTI]

    Radiometer and Inter-Comparison with CIMEL Sun Photometer and MICROTOPS Sun Photometer Antonio Aguirre Radiometer (MFRSR) and comparing with data from a CIMEL Sun Photometer and a MICROTOPS Sun Photometer. Using the inverse cosine of the angle between the sun and the vertical. A Langley plot provides a linear regression

  9. ARM - Campaign Instrument - mfrsr

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  10. ARM - Datastreams - mfrsr

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  11. ARM - Instrument - mfrsr

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  12. Retrieval of Areal-averaged Spectral Surface Albedo from Transmission Data Alone: Computationally Simple and Fast Approach

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Barnard, James C.; Flynn, Connor J.; Riihimaki, Laura D.; Michalsky, Joseph; Hodges, G. B.

    2014-10-25T23:59:59.000Z

    We introduce and evaluate a simple retrieval of areal-averaged surface albedo using ground-based measurements of atmospheric transmission alone at five wavelengths (415, 500, 615, 673 and 870nm), under fully overcast conditions. Our retrieval is based on a one-line semi-analytical equation and widely accepted assumptions regarding the weak spectral dependence of cloud optical properties, such as cloud optical depth and asymmetry parameter, in the visible and near-infrared spectral range. To illustrate the performance of our retrieval, we use as input measurements of spectral atmospheric transmission from Multi-Filter Rotating Shadowband Radiometer (MFRSR). These MFRSR data are collected at two well-established continental sites in the United States supported by the U.S. Department of Energy’s (DOE’s) Atmospheric Radiation Measurement (ARM) Program and National Oceanic and Atmospheric Administration (NOAA). The areal-averaged albedos obtained from the MFRSR are compared with collocated and coincident Moderate Resolution Imaging Spectroradiometer (MODIS) white-sky albedo. In particular, these comparisons are made at four MFRSR wavelengths (500, 615, 673 and 870nm) and for four seasons (winter, spring, summer and fall) at the ARM site using multi-year (2008-2013) MFRSR and MODIS data. Good agreement, on average, for these wavelengths results in small values (?0.01) of the corresponding root mean square errors (RMSEs) for these two sites. The obtained RMSEs are comparable with those obtained previously for the shortwave albedos (MODIS-derived versus tower-measured) for these sites during growing seasons. We also demonstrate good agreement between tower-based daily-averaged surface albedos measured for “nearby” overcast and non-overcast days. Thus, our retrieval originally developed for overcast conditions likely can be extended for non-overcast days by interpolating between overcast retrievals.

  13. Temporal Variability of Aerosol Properties during TCAP: Impact on Radiative Forcing

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Fast, Jerome D.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

    2013-11-01T23:59:59.000Z

    Ground-based remote sensing and in situ observations of aerosol microphysical and optical properties have been collected during summertime (June-August, 2012) as part of the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/), which was supported by the U.S. Department of Energy’s (DOE’s) Atmospheric Radiation Measurement (ARM) Program (http://www.arm.gov/). The overall goal of the TCAP field campaign is to study the evolution of optical and microphysical properties of atmospheric aerosol transported from North America to the Atlantic and their impact on the radiation energy budget. During TCAP, the ground-based ARM Mobile Facility (AMF) was deployed on Cape Cod, an arm-shaped peninsula situated on the easternmost portion of Massachusetts (along the east coast of the United States) and that is generally downwind of large metropolitan areas. The AMF site was equipped with numerous instruments for sampling aerosol, cloud and radiative properties, including a Multi-Filter Rotating Shadowband Radiometer (MFRSR), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS), and a three-wavelength nephelometer. In this study we present an analysis of diurnal and day-to-day variability of the column and near-surface aerosol properties obtained from remote sensing (MFRSR data) and ground-based in situ measurements (SMPS, APS, and nephelometer data). In particular, we show that the observed diurnal variability of the MFRSR aerosol optical depth is strong and comparable with that obtained previously from the AERONET climatology in Mexico City, which has a larger aerosol loading. Moreover, we illustrate how the variability of aerosol properties impacts the direct aerosol radiative forcing at different time scales.

  14. ARM - Campaign Instrument - uv-mfrsr

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  15. Automated Algorithm for MFRSR Data Analysis

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  16. Diamagnetism of rotating plasma

    SciTech Connect (OSTI)

    Young, W. C.; Hassam, A. B.; Romero-Talamas, C. A.; Ellis, R. F.; Teodorescu, C. [IREAP, University of Maryland, College Park, Maryland 20742 (United States)

    2011-11-15T23:59:59.000Z

    Diamagnetism and magnetic measurements of a supersonically rotating plasma in a shaped magnetic field demonstrate confinement of plasma pressure along the magnetic field resulting from centrifugal force. The Grad-Shafranov equation of ideal magnetohydrodynamic force balance, including supersonic rotation, is solved to confirm that the predicted angular velocity is in agreement with spectroscopic measurements of the Doppler shifts.

  17. Rotational cavity optomechanics

    E-Print Network [OSTI]

    Bhattacharya, M

    2015-01-01T23:59:59.000Z

    We theoretically examine the optomechanical interaction between a rotating nanoparticle and an orbital angular momentum-carrying optical cavity mode. Specifically, we consider a dielectric nanosphere rotating uniformly in a ring-shaped optical potential inside a Fabry-Perot resonator. The motion of the particle is probed by a weak angular lattice, created by introducing two additional degenerate Laguerre-Gaussian cavity modes carrying equal and opposite orbital angular momenta. We demonstrate that the rotation frequency of the nanoparticle is imprinted on the probe optical mode, via the Doppler shift, and thus may be sensed experimentally using homodyne detection. We show analytically that the effect of the optical probe on the particle rotation vanishes in the regime of linear response, resulting in an accurate frequency measurement. We also numerically characterize the degradation of the measurement accuracy when the system is driven in the nonlinear regime. Our results are relevant to rotational Doppler ve...

  18. A Rotating Holographic Superconductor

    E-Print Network [OSTI]

    Julian Sonner

    2009-03-31T23:59:59.000Z

    In this paper we initiate the study of SSB in 3+1 dimensional rotating, charged, asymptotically AdS black holes. The theory living on their boundary, R x S^2, has the interpretation of a 2+1 dimensional rotating holographic superconductor. We study the appearance of a marginal mode of the condensate as the temperature is decreased. We find that the transition temperature depends on the rotation. At temperatures just below T_c, the transition temperature at zero rotation, there exists a critical value of the rotation, which destroys the superconducting order. This behaviour is analogous to the emergence of a critical applied magnetic field and we show that the superconductor in fact produces the expected London field in the planar limit.

  19. Rotating holographic superconductor

    SciTech Connect (OSTI)

    Sonner, Julian [Blackett Laboratory, Imperial College, London, SW7 2AZ (United Kingdom) and Trinity College, University of Cambridge, Cambridge, CB2 1TQ (United Kingdom)

    2009-10-15T23:59:59.000Z

    In this paper we initiate the study of spontaneous symmetry breaking in 3+1 dimensional rotating, charged, asymptotically AdS black holes. The theory living on their boundary, RxS{sup 2}, has the interpretation of a 2+1 dimensional rotating holographic superconductor. We study the appearance of a marginal mode of the condensate as the temperature is decreased. We find that the transition temperature depends on the rotation. At temperatures just below T{sub c}, the transition temperature at zero rotation, there exists a critical value of the rotation, which destroys the superconducting order. This behavior is analogous to the emergence of a critical applied magnetic field and we show that the superconductor in fact produces the expected London field in the planar limit.

  20. ROTATING GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Bianchini, P.; Varri, A. L. [Now at Department of Astronomy, Indiana University, 727 East 3rd Street, Swain West 319, Bloomington, IN 47405-7105 (United States); Bertin, G.; Zocchi, A., E-mail: bianchini@mpia.de [Dipartimento di Fisica, Universita degli Studi di Milano, via Celoria 16, I-20133 Milano (Italy)

    2013-07-20T23:59:59.000Z

    Internal rotation is thought to play a major role in the dynamics of some globular clusters. However, in only a few cases has internal rotation been studied by the quantitative application of realistic and physically justified global models. Here, we present a dynamical analysis of the photometry and three-dimensional kinematics of {omega} Cen, 47 Tuc, and M15, by means of a recently introduced family of self-consistent axisymmetric rotating models. The three clusters, characterized by different relaxation conditions, show evidence of differential rotation and deviations from sphericity. The combination of line-of-sight velocities and proper motions allows us to determine their internal dynamics, predict their morphology, and estimate their dynamical distance. The well-relaxed cluster 47 Tuc is interpreted very well by our model; internal rotation is found to explain the observed morphology. For M15, we provide a global model in good agreement with the data, including the central behavior of the rotation profile and the shape of the ellipticity profile. For the partially relaxed cluster {omega} Cen, the selected model reproduces the complex three-dimensional kinematics; in particular, the observed anisotropy profile, characterized by a transition from isotropy to weakly radial anisotropy and then to tangential anisotropy in the outer parts. The discrepancy found for the steep central gradient in the observed line-of-sight velocity dispersion profile and for the ellipticity profile is ascribed to the condition of only partial relaxation of this cluster and the interplay between rotation and radial anisotropy.

  1. Rotational Quantum Friction

    E-Print Network [OSTI]

    Rongkuo Zhao; Alejandro Manjavacas; F. Javier García de Abajo; J. B. Pendry

    2012-09-25T23:59:59.000Z

    We investigate the frictional forces due to quantum fluctuations acting on a small sphere rotating near a surface. At zero temperature, we find the frictional force near a surface to be several orders of magnitude larger than that for the sphere rotating in vacuum. For metallic materials with typical conductivity, quantum friction is maximized by matching the frequency of rotation with the conductivity. Materials with poor conductivity are favored to obtain large quantum frictions. For semiconductor materials that are able to support surface plasmon polaritons, quantum friction can be further enhanced by several orders of magnitude due to the excitation of surface plasmon polaritons.

  2. Algebra of Rotations

    E-Print Network [OSTI]

    Donu Arapura

    2013-01-07T23:59:59.000Z

    Chapter 1. Algebra of Rotations. One of our goals is to make precise the idea of symmetry, which is important in math and other parts of science. Something like ...

  3. Rotational rate sensor

    DOE Patents [OSTI]

    Hunter, Steven L. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A rate sensor for angular/rotational acceleration includes a housing defining a fluid cavity essentially completely filled with an electrolyte fluid. Within the housing, such as a toroid, ions in the fluid are swept during movement from an excitation electrode toward one of two output electrodes to provide a signal for directional rotation. One or more ground electrodes within the housing serve to neutralize ions, thus preventing any effect at the other output electrode.

  4. Electromagnetic rotational actuation.

    SciTech Connect (OSTI)

    Hogan, Alexander Lee

    2010-08-01T23:59:59.000Z

    There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.

  5. Rotating arc spark plug

    DOE Patents [OSTI]

    Whealton, John H.; Tsai, Chin-Chi

    2003-05-27T23:59:59.000Z

    A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

  6. Faraday rotation in graphene

    E-Print Network [OSTI]

    I. V. Fialkovsky; D. V. Vassilevich

    2012-11-29T23:59:59.000Z

    We study magneto--optical properties of monolayer graphene by means of quantum field theory methods in the framework of the Dirac model. We reveal a good agreement between the Dirac model and a recent experiment on giant Faraday rotation in cyclotron resonance. We also predict other regimes when the effects are well pronounced. The general dependence of the Faraday rotation and absorption on various parameters of samples is revealed both for suspended and epitaxial graphene.

  7. Rotating Aperture System

    DOE Patents [OSTI]

    Rusnak, Brian (Livermore, CA); Hall, James M. (Livermore, CA); Shen, Stewart (Danville, CA); Wood, Richard L. (Santa Fe, NM)

    2005-01-18T23:59:59.000Z

    A rotating aperture system includes a low-pressure vacuum pumping stage with apertures for passage of a deuterium beam. A stator assembly includes holes for passage of the beam. The rotor assembly includes a shaft connected to a deuterium gas cell or a crossflow venturi that has a single aperture on each side that together align with holes every rotation. The rotating apertures are synchronized with the firing of the deuterium beam such that the beam fires through a clear aperture and passes into the Xe gas beam stop. Portions of the rotor are lapped into the stator to improve the sealing surfaces, to prevent rapid escape of the deuterium gas from the gas cell.

  8. Rotating bubble membrane radiator

    DOE Patents [OSTI]

    Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

    1988-12-06T23:59:59.000Z

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  9. Rotating Hairy Black Holes

    E-Print Network [OSTI]

    B. Kleihaus; J. Kunz

    2000-12-20T23:59:59.000Z

    We construct stationary black holes in SU(2) Einstein-Yang-Mills theory, which carry angular momentum and electric charge. Possessing non-trivial non-abelian magnetic fields outside their regular event horizon, they represent non-perturbative rotating hairy black holes.

  10. Rotatable stem and lock

    DOE Patents [OSTI]

    Deveney, J.E.; Sanderson, S.N.

    1981-10-27T23:59:59.000Z

    A valve stem and lock is disclosed which includes a housing surrounding a valve stem, a solenoid affixed to an interior wall of the housing, an armature affixed to the valve stem and a locking device for coupling the armature to the housing body. When the solenoid is energized, the solenoid moves away from the housing body, permitting rotation of the valve stem.

  11. FORMULATION OF ROTATIONAL SYSTEMS

    E-Print Network [OSTI]

    , by formulating a rotational equivalent mass called "moment of inertia." 3.1 Newton's Law Revisited Let us begin Figure 3.2: Simple Pendulum with Torsion Spring for T to obtain Newton's law in units of torque: T = (mr2 gravitational term as the crude analysis of Section ??, but now we know the magnitude of the terms we have

  12. The Rotating Quantum Vacuum

    E-Print Network [OSTI]

    Paul C. W. Davies; Tevian Dray; Corinne A. Manogue

    1996-01-22T23:59:59.000Z

    We derive conditions for rotating particle detectors to respond in a variety of bounded spacetimes and compare the results with the folklore that particle detectors do not respond in the vacuum state appropriate to their motion. Applications involving possible violations of the second law of thermodynamics are briefly addressed.

  13. Wave-driven Rotation in Supersonically Rotating Mirrors

    SciTech Connect (OSTI)

    A. Fetterman and N.J. Fisch

    2010-02-15T23:59:59.000Z

    Supersonic rotation in mirrors may be produced by radio frequency waves. The waves produce coupled diffusion in ion kinetic and potential energy. A population inversion along the diffusion path then produces rotation. Waves may be designed to exploit a natural kinetic energy source or may provide the rotation energy on their own. Centrifugal traps for fusion and isotope separation may benefit from this wave-driven rotation.

  14. Clinical Rotation Descriptions-2013 Clinical Rotation Description Forms the Student

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Clinical Rotation Descriptions- 2013 Clinical Rotation Description Forms the Student Completes:1 with a PT 2 from rotation (3), allowing the PT 2 to teach the PT 1. GAs * at end of experience, Clinical Performance Evaluation, Physical Therapy Student Evaluation: Clinical Experience and Instruction 1 page form

  15. A Novel Retrieval Algorithm for Cloud Optical Properties from the Atmopsheric Radiation Measurement Program's Two-Channel Narrow-Field-of-View Radiometer

    SciTech Connect (OSTI)

    Wiscombe, Warren J.; Marshak, A.; Chiu, J.-Y. C.; Knyazikhin, Y.; Barnard, James C.; Luo, Yi

    2005-03-14T23:59:59.000Z

    Cloud optical depth is the most important of all cloud optical properties, and vital for any cloud-radiation parameterization. To estimate cloud optical depth, the atmospheric science community has widely used ground-based flux measurements from either broadband or narrowband radiometers in the past decade. However, this type of technique is limited to overcast conditions and, at best, gives us an "effective" cloud optical depth instead of its "local" value. Unlike flux observations, monochromatic narrow-field-of-view (NFOV) radiance measurements contain information of local cloud properties, but unfortunately, the use of radiance to interpret optical depth suffers from retrieval ambiguity. We have pioneered an algorithm to retrieve cloud optical depth in a fully three-dimensional cloud situation using new Atmospheric Radiation Measurement (ARM) ground-based passive two-channel (673 and 870 nm) NFOV measurements. The underlying principle of the algorithm is that these two channels have similar cloud properties but strong spectral contrast in surface reflectance. This algorthm offers the first opportunity to illustrate cloud evolution with high temporal resolution retrievals. A combination of two-channel NFOV radiances with multi-filter rotating shadowband radiometer (MFRSR) fluxes for the retrieval of cloud optical properties is also discussed.

  16. Sample rotating turntable kit for infrared spectrometers

    DOE Patents [OSTI]

    Eckels, Joel Del (Livermore, CA); Klunder, Gregory L. (Oakland, CA)

    2008-03-04T23:59:59.000Z

    An infrared spectrometer sample rotating turntable kit has a rotatable sample cup containing the sample. The infrared spectrometer has an infrared spectrometer probe for analyzing the sample and the rotatable sample cup is adapted to receive the infrared spectrometer probe. A reflectance standard is located in the rotatable sample cup. A sleeve is positioned proximate the sample cup and adapted to receive the probe. A rotator rotates the rotatable sample cup. A battery is connected to the rotator.

  17. Rotating drum filter

    DOE Patents [OSTI]

    Anson, Donald (Worthington, OH)

    1990-01-01T23:59:59.000Z

    A perforated drum (10) rotates in a coaxial cylindrical housing (18) having three circumferential ports (19,22,23), and an axial outlet (24) at one end. The axis (11) is horizontal. A fibrous filter medium (20) is fed through a port (19) on or near the top of the housing (81) by a distributing mechanism (36) which lays a uniform mat (26) of the desired thickness onto the rotating drum (10). This mat (26) is carried by the drum (10) to a second port (23) through which dirty fluid (13) enters. The fluid (13) passes through the filter (26) and the cleaned stream (16) exits through the open end (15) of the drum (10) and the axial port (24) in the housing (18). The dirty filter material (20) is carried on to a third port (22) near the bottom of the housing (18) and drops into a receiver (31) from which it is continuously removed, cleaned (30), and returned (32) to the charging port (36) at the top. To support the filter mat, the perforated cylinder may carry a series of tines (40), shaped blades (41), or pockets, so that the mat (26) will not fall from the drum (10) prematurely. To minimize risk of mat failure, the fluid inlet port (23) may be located above the horizontal centerline (11).

  18. Digital rotation measurement unit

    DOE Patents [OSTI]

    Sanderson, S.N.

    1983-09-30T23:59:59.000Z

    A digital rotation indicator is disclosed for monitoring the position of a valve member having a movable actuator. The indicator utilizes mercury switches adapted to move in cooperation with the actuator. Each of the switches produces an output as it changes state when the actuator moves. A direction detection circuit is connected to the switches to produce a first digital signal indicative of the direction of rotation of the actuator. A count pulse generating circuit is also connected to the switches to produce a second digital pulse signal having count pulses corresponding to a change of state of any of the mercury switches. A reset pulse generating circuit is provided to generate a reset pulse each time a count pulse is generated. An up/down counter is connected to receive the first digital pulse signal and the second digital pulse signal and to count the pulses of the second digital pulse signal either up or down depending upon the instantaneous digital value of the first digital signal whereby a running count indicative of the movement of the actuator is maintained.

  19. Slowly rotating homogeneous masses revisited

    E-Print Network [OSTI]

    Reina, Borja

    2015-01-01T23:59:59.000Z

    Hartle's model for slowly rotating stars has been extensively used to compute equilibrium configurations of slowly rotating stars to second order in perturbation theory in General Relativity, given a barotropic equation of state (EOS). A recent study based on the modern theory of perturbed matchings show that the model must be amended to accommodate EOS's in which the energy density does not vanish at the surface of the non rotating star. In particular, the expression for the change in mass given in the original model, i.e. a contribution to the mass that arises when the perturbations are chosen so that the pressure of the rotating and non rotating configurations agree, must be modified with an additional term. In this paper, the amended change in mass is calculated for the case of constant density stars.

  20. Rotational response of superconductors: magneto-rotational isomorphism and rotation-induced vortex lattice

    E-Print Network [OSTI]

    Egor Babaev; Boris Svistunov

    2014-03-03T23:59:59.000Z

    The analysis of nonclassical rotational response of superfluids and superconductors was performed by Onsager (in 1949) \\cite{Onsager} and London (in 1950) \\cite{London} and crucially advanced by Feynman (in 1955) \\cite{Feynman}. It was established that, in thermodynamic limit, neutral superfluids rotate by forming---without any threshold---a vortex lattice. In contrast, the rotation of superconductors at angular frequency ${\\bf \\Omega}$---supported by uniform magnetic field ${\\bf B}_L\\propto {\\bf \\Omega}$ due to surface currents---is of the rigid-body type (London Law). Here we show that, neglecting the centrifugal effects, the behavior of a rotating superconductor is identical to that of a superconductor placed in a uniform fictitious external magnetic filed $\\tilde{\\bf H}=- {\\bf B}_L$. In particular, the isomorphism immediately implies the existence of two critical rotational frequencies in type-2 superconductors.

  1. Cooling system for rotating machine

    DOE Patents [OSTI]

    Gerstler, William Dwight (Niskayuna, NY); El-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Lokhandwalla, Murtuza (Clifton Park, NY); Alexander, James Pellegrino (Ballston Lake, NY); Quirion, Owen Scott (Clifton Park, NY); Palafox, Pepe (Schenectady, NY); Shen, Xiaochun (Schenectady, NY); Salasoo, Lembit (Schenectady, NY)

    2011-08-09T23:59:59.000Z

    An electrical machine comprising a rotor is presented. The electrical machine includes the rotor disposed on a rotatable shaft and defining a plurality of radial protrusions extending from the shaft up to a periphery of the rotor. The radial protrusions having cavities define a fluid path. A stationary shaft is disposed concentrically within the rotatable shaft wherein an annular space is formed between the stationary and rotatable shaft. A plurality of magnetic segments is disposed on the radial protrusions and the fluid path from within the stationary shaft into the annular space and extending through the cavities within the radial protrusions.

  2. ARM - Campaign Instrument - mfrsr-wv1barn

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492air Comments? We would love to hear from you! SendgovInstrumentslmwrr-air Comments?barn Comments? We

  3. ARM - Campaign Instrument - mfrsr-wv1mich

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  4. ARM - Evaluation Product - Cloud Optical Properties from MFRSR Using Min

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m Documentation DataDatastreamsxsaprhsrhi1-min (NAVBE1M)

  5. ARM - Evaluation Product - MFRSR-Column Intensive Properties

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  6. ARM - PI Product - 1.6 Micron MFRSR

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat fluxChinaNews : AMFAlaskaNewsOxides ofProducts1.6

  7. ARM - PI Product - Aerosol Retrievals from ARM SGP MFRSR Data

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDCnarrowbandheat fluxChinaNews :ProductsAerosol Retrievals from ARM

  8. MFRSR Head Refurbishment, Data Logger Upgrade and Calibration Improvements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, In this3,OfficeWITH AT LEASTThe

  9. On Correction of Diffuse Radiation Measured by MFRSR

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeeding accessSpeedingOctoberResearch &CEATOmar Hurricane,Physics ofOn

  10. Rotational Mixing and Lithium Depletion

    E-Print Network [OSTI]

    Pinsonneault, M H

    2010-01-01T23:59:59.000Z

    I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time. New developments related to the possible suppression of mixing at late ages, close binary mergers and their lithium signature, and an alternate origin for dispersion in young cool stars tied to radius anomalies observed in active young stars are discussed. I highlight uncertainties in models of Population II lithium depletion and dispersion related to the treatment of angular momentum loss. Finally, the origins of rotation are tied to conditions in the pre-main sequence, and there is thus some evidence that enviroment and planet formation could impact stellar rotational properties. This may be related to recent observational evidence for cluster to cluster variations in lithium depletion and a connection between the presence of planets and s...

  11. Rotational dynamics of entangled polymers

    E-Print Network [OSTI]

    Jean-Charles Walter; Michiel Laleman; Marco Baiesi; Enrico Carlon

    2014-09-01T23:59:59.000Z

    Some recent results on the rotational dynamics of polymers are reviewed and extended. We focus here on the relaxation of a polymer, either flexible or semiflexible, initially wrapped around a rigid rod. We also study the steady polymer rotation generated by a constant torque on the rod. The interplay of frictional and entropic forces leads to a complex dynamical behavior characterized by non-trivial universal exponents. The results are based on extensive simulations of polymers undergoing Rouse dynamics and on an analytical approach using force balance and scaling arguments. The analytical results are in general in good agreement with the simulations, showing how a simplified approach can correctly capture the complex dynamical behavior of rotating polymers.

  12. Vacuum friction in rotating particles

    E-Print Network [OSTI]

    A. Manjavacas; F. J. García de Abajo

    2010-09-21T23:59:59.000Z

    We study the frictional torque acting on particles rotating in empty space. At zero temperature, vacuum friction transforms mechanical energy into light emission and produces particle heating. However, particle cooling relative to the environment occurs at finite temperatures and low rotation velocities. Radiation emission is boosted and its spectrum significantly departed from a hot-body emission profile as the velocity increases. Stopping times ranging from hours to billions of years are predicted for materials, particle sizes, and temperatures accessible to experiment. Implications for the behavior of cosmic dust are discussed.

  13. Mechanics of Rotating Isolated Horizons

    E-Print Network [OSTI]

    Abhay Ashtekar; Christopher Beetle; Jerzy Lewandowski

    2001-04-11T23:59:59.000Z

    Black hole mechanics was recently extended by replacing the more commonly used event horizons in stationary space-times with isolated horizons in more general space-times (which may admit radiation arbitrarily close to black holes). However, so far the detailed analysis has been restricted to non-rotating black holes (although it incorporated arbitrary distortion, as well as electromagnetic, Yang-Mills and dilatonic charges). We now fill this gap by first introducing the notion of isolated horizon angular momentum and then extending the first law to the rotating case.

  14. Rotating drum variable depth sampler

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC); Steeper, Timothy J. (Trenton, SC)

    2008-07-01T23:59:59.000Z

    A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

  15. Rotationally invariant multilevel block codes

    E-Print Network [OSTI]

    Kulandaivelu, Anita

    1993-01-01T23:59:59.000Z

    The objective of this thesis is to evaluate the performance of block codes that are designed to be rotationally invariant, in a multilevel coding scheme, over a channel modelled to be white gaussian noise. Also, the use of non-binary codes...

  16. Rotational ratchets with dipolar interactions

    E-Print Network [OSTI]

    Sebastian Jäger; Sabine H. L. Klapp

    2012-10-12T23:59:59.000Z

    We report results from a computer simulation study on the rotational ratchet effect in systems of magnetic particles interacting via dipolar interactions. The ratchet effect consists of directed rotations of the particles in an oscillating magnetic field, which lacks a net rotating component. Our investigations are based on Brownian dynamics simulations of such many-particle systems. We investigate the influence of both, the random and deterministic contributions to the equations of motion on the ratchet effect. As a main result, we show that dipolar interactions can have an enhancing as well as a dampening effect on the ratchet behavior depending on the dipolar coupling strength of the system under consideration. The enhancement is shown to be caused by an increase in the effective field on a particle generated by neighboring magnetic particles, while the dampening is due to restricted rotational motion in the effective field. Moreover, we find a non-trivial influence of the short-range, repulsive interaction between the particles.

  17. Impact of plasma poloidal rotation on resistive wall mode instability in toroidally rotating plasmas

    SciTech Connect (OSTI)

    Aiba, N.; Shiraishi, J. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Tokuda, S. [Research Organization for Information Science and Technology, Kita-Shinagawa, Shinagawa, Tokyo 140-0001 (Japan)

    2011-02-15T23:59:59.000Z

    Stability of resistive wall mode (RWM) is investigated in a cylindrical plasma and an axisymmetric toroidal plasma by taking into account not only toroidal rotation but also poloidal rotation. Since the Doppler shifted frequency is responsible for the RWM stability, the modification of this Doppler shifted frequency by poloidal rotation affects the rotation effect on RWM. When a poloidal rotation frequency is not so large, the effect of poloidal rotation on the RWM stability can be approximately treated with the modified toroidal rotation frequency. In a toroidal plasma, this modified frequency is determined by subtracting a toroidal component of the rotation parallel to the magnetic field from the toroidal rotation frequency. The poloidal rotation that counteracts the effect of the Doppler shift strongly reduces the stabilizing effect of toroidal rotation, but by changing the rotational direction, the poloidal rotation enhances this stabilizing effect. This trend is confirmed in not only a cylindrical plasma but also a toroidal plasma. This result indicates that poloidal rotation produces the dependence of the critical toroidal rotation frequency for stabilizing RWM on the rotational direction of toroidal rotation in the same magnetic configuration.

  18. Rotation generation and transport in tokamak plasmas

    E-Print Network [OSTI]

    Podpaly, Yuri Anatoly

    2012-01-01T23:59:59.000Z

    Plasma toroidal rotation is a factor important for plasma stability and transport, but it is still a fairly poorly understood area of physics. This thesis focuses on three aspects of rotation: momentum transport, Ohmic ...

  19. Experiments with Fertilizers on Rotated and Non-Rotated Crops.

    E-Print Network [OSTI]

    Reynolds, E. B. (Elbert Brunner)

    1928-01-01T23:59:59.000Z

    This is a report of experiments conducted over a period of 14 years to study the effect of fertilizers, manure, removal. of crop residues, and rota- tion on the yield of crops. The fertilizer treatments included superphos- phate; superphosphate and manure...; superphosphate and cottonseed meal; manure; rock phosphate; and rock phosphate and manure. Cotton and corn were grown continuously on the same land and in rotation with oats and cowpeas. The soil responded more readily to nitrogenous than to phosphatic fer...

  20. Gravity controlled anti-reverse rotation device

    DOE Patents [OSTI]

    Dickinson, Robert J. (Shaler Township, Allegheny County, PA); Wetherill, Todd M. (Lower Burrell, PA)

    1983-01-01T23:59:59.000Z

    A gravity assisted anti-reverse rotation device for preventing reverse rotation of pumps and the like. A horizontally mounted pawl is disposed to mesh with a fixed ratchet preventing reverse rotation when the pawl is advanced into intercourse with the ratchet by a vertically mounted lever having a lumped mass. Gravitation action on the lumped mass urges the pawl into mesh with the ratchet, while centrifugal force on the lumped mass during forward, allowed rotation retracts the pawl away from the ratchet.

  1. On the Energy of Rotating Gravitational Waves

    E-Print Network [OSTI]

    Bahram Mashhoon; James C. McClune; Enrique Chavez; Hernando Quevedo

    1996-09-06T23:59:59.000Z

    A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.

  2. Rotating concave eddy current probe

    SciTech Connect (OSTI)

    Roach, Dennis P. (Albuquerque, NM); Walkington, Phil (Albuquerque, NM); Rackow, Kirk A. (Albuquerque, NM); Hohman, Ed (Albuquerque, NM)

    2008-04-01T23:59:59.000Z

    A rotating concave eddy current probe for detecting fatigue cracks hidden from view underneath the head of a raised head fastener, such as a buttonhead-type rivet, used to join together structural skins, such as aluminum aircraft skins. The probe has a recessed concave dimple in its bottom surface that closely conforms to the shape of the raised head. The concave dimple holds the probe in good alignment on top of the rivet while the probe is rotated around the rivet's centerline. One or more magnetic coils are rigidly embedded within the probe's cylindrical body, which is made of a non-conducting material. This design overcomes the inspection impediment associated with widely varying conductivity in fastened joints.

  3. Particle entanglement in rotating gases

    SciTech Connect (OSTI)

    Liu Zhao; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-06-15T23:59:59.000Z

    In this paper, we investigate the particle entanglement in two-dimensional (2D) weakly interacting rotating Bose and Fermi gases. We find that both particle localization and vortex localization can be indicated by particle entanglement. We also use particle entanglement to show the occurrence of edge reconstruction of rotating fermions. The different properties of condensate phase and vortex liquid phase of bosons can be reflected by particle entanglement and in vortex liquid phase we construct the same trial wave function with that in [Phys. Rev. Lett. 87, 120405 (2001)] from the viewpoint of entanglement to relate the ground state with quantum Hall state. Finally, the relation between particle entanglement and interaction strength is studied.

  4. Gravitational duality and rotating solutions

    SciTech Connect (OSTI)

    Argurio, Riccardo; Dehouck, Francois [Physique Theorique et Mathematique and International Solvay Institutes, Universite Libre de Bruxelles, C.P. 231, 1050 Bruxelles (Belgium)

    2010-03-15T23:59:59.000Z

    We study how gravitational duality acts on rotating solutions, using the Kerr-NUT black hole as an example. After properly reconsidering how to take into account both electric (i.e. masslike) and magnetic (i.e. NUT-like) sources in the equations of general relativity, we propose a set of definitions for the dual Lorentz charges. We then show that the Kerr-NUT solution has nontrivial such charges. Further, we clarify in which respect Kerr's source can be seen as a mass M with a dipole of NUT charges.

  5. Dual rotating shaft seal apparatus

    DOE Patents [OSTI]

    Griggs, J.E.; Newman, H.J.

    1983-06-16T23:59:59.000Z

    The report is directed to apparatus suitable for transferring torque and rotary motion through a wall in a manner which is essentially gas impermeable. The apparatus can be used for pressurizing, agitating, and mixing fluids and features two ferrofluidic, i.e., ferrometic seals. Each seal is disposed on one of two supported shafts and each shaft is operably connected at one end to a gear mechanism and at its other end to an adjustable coupling means which is to be connected to a rotatable shaft extending through a wall through which torque and rotary motion are to be transferred.

  6. Trirotron: triode rotating beam radio frequency amplifier

    DOE Patents [OSTI]

    Lebacqz, Jean V. (Stanford, CA)

    1980-01-01T23:59:59.000Z

    High efficiency amplification of radio frequencies to very high power levels including: establishing a cylindrical cloud of electrons; establishing an electrical field surrounding and coaxial with the electron cloud to bias the electrons to remain in the cloud; establishing a rotating electrical field that surrounds and is coaxial with the steady field, the circular path of the rotating field being one wavelength long, whereby the peak of one phase of the rotating field is used to accelerate electrons in a beam through the bias field in synchronism with the peak of the rotating field so that there is a beam of electrons continuously extracted from the cloud and rotating with the peak; establishing a steady electrical field that surrounds and is coaxial with the rotating field for high-energy radial acceleration of the rotating beam of electrons; and resonating the rotating beam of electrons within a space surrounding the second field, the space being selected to have a phase velocity equal to that of the rotating field to thereby produce a high-power output at the frequency of the rotating field.

  7. Areal-averaged and Spectrally-resolved Surface Albedo from Ground-based Transmission Data Alone: Toward an Operational Retrieval

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Barnard, James C.; Flynn, Connor J.; Riihimaki, Laura D.; Michalsky, Joseph; Hodges, G. B.

    2014-08-22T23:59:59.000Z

    We present here a simple retrieval of the areal-averaged and spectrally resolved surface albedo using only ground-based measurements of atmospheric transmission under fully overcast conditions. Our retrieval is based on a one-line equation and widely accepted assumptions regarding the weak spectral dependence of cloud optical properties in the visible and near-infrared spectral range. The feasibility of our approach for the routine determinations of albedo is demonstrated for different landscapes with various degrees of heterogeneity using three sets of measurements:(1) spectrally resolved atmospheric transmission from Multi-Filter Rotating Shadowband Radiometer (MFRSR) at wavelength 415, 500, 615, 673, and 870 nm, (2) tower-based measurements of local surface albedo at the same wavelengths, and (3) areal-averaged surface albedo at four wavelengths (470, 560, 670 and 860 nm) from collocated and coincident Moderate Resolution Imaging Spectroradiometer (MODIS) observations. These integrated datasets cover both long (2008-2013) and short (April-May, 2010) periods at the ARM Southern Great Plains (SGP) site and the NOAA Table Mountain site, respectively. The calculated root mean square error (RMSE), which is defined here as the root mean squared difference between the MODIS-derived surface albedo and the retrieved area-averaged albedo, is quite small (RMSE?0.01) and comparable with that obtained previously by other investigators for the shortwave broadband albedo. Good agreement between the tower-based daily averages of surface albedo for the completely overcast and non-overcast conditions is also demonstrated. This agreement suggests that our retrieval originally developed for the overcast conditions likely will work for non-overcast conditions as well.

  8. Inertial measurement unit using rotatable MEMS sensors

    DOE Patents [OSTI]

    Kohler, Stewart M.; Allen, James J.

    2006-06-27T23:59:59.000Z

    A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator for drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows, for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

  9. Inertial measurement unit using rotatable MEMS sensors

    DOE Patents [OSTI]

    Kohler, Stewart M. (Albuquerque, NM); Allen, James J. (Albuquerque, NM)

    2007-05-01T23:59:59.000Z

    A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

  10. Contained Modes In Mirrors With Sheared Rotation

    SciTech Connect (OSTI)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2010-10-08T23:59:59.000Z

    In mirrors with E × B rotation, a fixed azimuthal perturbation in the lab frame can appear as a wave in the rotating frame. If the rotation frequency varies with radius, the plasma-frame wave frequency will also vary radially due to the Doppler shift. A wave that propagates in the high rotation plasma region might therefore be evanescent at the plasma edge. This can lead to radially localized Alfven eigenmodes with high azimuthal mode numbers. Contained Alfven modes are found both for peaked and non-peaked rotation profiles. These modes might be useful for alpha channeling or ion heating, as the high azimuthal wave number allows the plasma wave frequency in the rotating frame to exceed the ion cyclotron frequency. __________________________________________________

  11. The Impact of Rotation on Cluster Dynamics

    E-Print Network [OSTI]

    Christian Boily

    2000-02-23T23:59:59.000Z

    The evolution of rotating, isolated clusters of stars up to core-collapse is investigated with n-body numerical codes. The simulations start off from axisymmetric generalisations of King profiles, with added global angular momentum. In this contribution I report on results obtained for two sets of single-mass cluster simulations. These confirm the more rapid evolution of even mildly-rotating clusters. A model is presented with rotational energy comparable to omega-Centauri's; it reaches core-collapse in less than half the time required for non-rotating model clusters.

  12. Control of molecular rotation in the limit of extreme rotational excitation

    E-Print Network [OSTI]

    Milner, V

    2015-01-01T23:59:59.000Z

    Laser control of molecular rotation is an area of active research. A number of recent studies has aimed at expanding the reach of rotational control to extreme, previously inaccessible rotational states, as well as controlling the directionality of molecular rotation. Dense ensembles of molecules undergoing ultrafast uni-directional rotation, known as molecular superrotors, are anticipated to exhibit unique properties, from spatially anisotropic diffusion and vortex formation to the creation of powerful acoustic waves and tuneable THz radiation. Here we describe our recent progress in controlling molecular rotation in the regime of high rotational excitation. We review two experimental techniques of producing uni-directional rotational wave packets with a "chiral train" of femtosecond pulses and an "optical centrifuge". Three complementary detection methods, enabling the direct observation, characterization and control of the superrotor states, are outlined: the one based on coherent Raman scattering, and two...

  13. Spontaneous generation of rotation in tokamak plasmas

    SciTech Connect (OSTI)

    Parra Diaz, Felix [Oxford University] [Oxford University

    2013-12-24T23:59:59.000Z

    Three different aspects of intrinsic rotation have been treated. i) A new, first principles model for intrinsic rotation [F.I. Parra, M. Barnes and P.J. Catto, Nucl. Fusion 51, 113001 (2011)] has been implemented in the gyrokinetic code GS2. The results obtained with the code are consistent with several experimental observations, namely the rotation peaking observed after an L-H transition, the rotation reversal observed in Ohmic plasmas, and the change in rotation that follows Lower Hybrid wave injection. ii) The model in [F.I. Parra, M. Barnes and P.J. Catto, Nucl. Fusion 51, 113001 (2011)] has several simplifying assumptions that seem to be satisfied in most tokamaks. To check the importance of these hypotheses, first principles equations that do not rely on these simplifying assumptions have been derived, and a version of these new equations has been implemented in GS2 as well. iii) A tokamak cross-section that drives large intrinsic rotation has been proposed for future large tokamaks. In large tokamaks, intrinsic rotation is expected to be very small unless some up-down asymmetry is introduced. The research conducted under this contract indicates that tilted ellipticity is the most efficient way to drive intrinsic rotation.

  14. Experimental and analytical study of rotating cavitation

    SciTech Connect (OSTI)

    Kamijo, Kenjiro; Shimura, Takashi; Tsujimoto, Yoshinobu [National Aerospace Lab., Miyagi (Japan). Kakuda Research Center

    1994-12-31T23:59:59.000Z

    This paper describes experimental and analytical results of rotating cavitation. There are four major sections in this paper. The first section presents the main characteristics of rotating cavitation which was found in the inducer test using a water tunnel. The second section describes the rotating cavitation which occurred in the development test of an LE-7 liquid oxygen pump for the H-II rocket. Also described in this section is how the rotating cavitation was suppressed. The rotating cavitation was the cause of both super synchronous shaft vibration and an unstable head coefficient curve. The third section presents how the theory of rotating cavitation was developed. The final section shows the measured cavitation compliance and mass flow gain factor of the LE-7 pump inducer for comparison of the experimental and analytical results of the rotating cavitation of the LE-7 pump inducer. Almost all the information presented in this paper has already been reported by Kamijo et al. (1977, 1980, 1993, 1993) and by Shimura (1993). In the present paper, the authors attempt to combine and give a clear overview of the experimental and analytical results described in the previous papers to systematically show their experience and findings on rotating cavitation.

  15. FIRST YEAR CLINIC ROTATIONS Inpatient unit

    E-Print Network [OSTI]

    Chapman, Michael S.

    FIRST YEAR CLINIC ROTATIONS Inpatient unit The fellow is responsible for the care and supervision weekly. Pediatric Hematology-Oncology Clinic The fellow on the PHO clinic rotation will be scheduled to evaluate scheduled clinic and infusion center patients along with an attending provider. Patients seen

  16. Computational Methods for High-Dimensional Rotations

    E-Print Network [OSTI]

    Buja, Andreas

    . To be useful, virtual rotations need to be under interactive user control, and they need to be animated. We scatters in virtual 3-D space. Although not obvivous, three-dimensional data rotations can be extended is due to the power of human 3-D perception and the natural controls they afford. To perform 3-D

  17. Holographic Superconductors in a Rotating Spacetime

    E-Print Network [OSTI]

    Kai Lin; Elcio Abdalla

    2014-10-17T23:59:59.000Z

    We consider holographic superconductors in a rotating black string spacetime. In view of the mandatory introduction of the $A_\\varphi$ component of the vector potential we are left with three equations to be solved. Their solutions show that the effect of the rotating parameter $a$ influences the critical temperature $T_c$ and the conductivity $\\sigma$ in a simple but not trivial way.

  18. Models of soft rotators and the theory of a harmonic rotator

    E-Print Network [OSTI]

    Zahid Zakir

    2012-12-12T23:59:59.000Z

    The states of a planar oscillator are separated to a vibrational mode, containing a zero-point energy, and a rotational mode without the zero-point energy, but having a conserved angular momentum. On the basis of the analysis of properties of models of rigid and semirigid rotators, the theory of soft rotators is formulated where the harmonic attractive force is balanced only by the centrifugal force. As examples a Coulomb rotator (the Bohr model) and a magneto-harmonic rotator (the Fock-Landau levels) are considered. Disappearance of the radial speed in the model of a magneto-harmonic rotator is taken as a defining property of a pure rotational motion in the harmonic potential. After the exception of energies of the magnetic and spin decompositions, specific to magnetic fields, one turns to a simple and general model of a planar harmonic rotator (circular oscillator without radial speed) where kinetic energy is reduced to the purely rotational energy. Energy levels of the harmonic rotator have the same frequency and are twice degenerate, the energy spectrum is equidistant. In the ground state there is no zero-point energy from rotational modes, and the zero-point energy of vibrational modes can be compensated by spin effects or symmetries of the system. In this case the operators of observables vanish the ground state, i.e. are "strongly" normally ordered. In a chain of harmonic rotators collective rotations around a common axis lead to transverse waves, at quantization of which there appear quasi-particles and holes carrying an angular momentum. In the chain SU(2) appears as a group of symmetry of a rotator.

  19. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

    2000-02-22T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  20. Analysis of Rotational Structure in the High-Resolution Infrared...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rotational Structure in the High-Resolution Infrared Spectrum and Assignment of Vibrational Fundamentals of Analysis of Rotational Structure in the High-Resolution Infrared...

  1. Testing Oxygen Reduction Reaction Activity with the Rotating...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique...

  2. Rotational Rehybridization and the High Temperature Phase of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rotational Rehybridization and the High Temperature Phase of UC2. Rotational Rehybridization and the High Temperature Phase of UC2. Abstract: The screened hybrid approximation...

  3. Rotational hysteresis of exchange-spring magnets.

    SciTech Connect (OSTI)

    Jiang, J.S.; Bader, S.D.; Kaper, H.; Leaf, G.K.; Shull, R.D.; Shapiro, A.J.; Gornakov, V.S.; Nikitenko, V.I.; Platt, C.L.; Berkowitz, A.E.; David, S.; Fullerton, E.E.

    2002-03-27T23:59:59.000Z

    We highlight our experimental studies and micromagnetic simulations of the rotational hysteresis in exchange-spring magnets. Magneto-optical imaging and torque magnetometry measurements for SmCo/Fe exchange-spring films with uniaxial in-plane anisotropy show that the magnetization rotation created in the magnetically soft Fe layer by a rotating magnetic field is hysteretic. The rotational hysteresis is due to the reversal of the chirality of the spin spiral structure. Micromagnetic simulations reveal two reversal modes of the chirality, one at low fields due to an in-plane untwisting of the spiral, and the other, at high fields, due to an out-of-plane fanning of the spiral.

  4. On rotationally driven meridional flows in stars

    E-Print Network [OSTI]

    P. Garaud

    2002-03-21T23:59:59.000Z

    A quasi-steady state model of the consequences of rotation on the hydrodynamical structure of a stellar radiative zone is derived, by studying in particular the role of centrifugal and baroclinic driving of meridional motions in angular-momentum transport. This nonlinear problem is solved numerically assuming axisymmetry of the system, and within some limits, it is shown that there exist simple analytical solutions. The limit of slow rotation recovers Eddington-Sweet theory, whereas it is shown that in the limit of rapid rotation, the system settles into a geostrophic equilibrium. The behaviour of the system is found to be controlled by one parameter only, linked to the Prantl number, the stratification and the rotation rate of the star.

  5. Collisional quenching of highly rotationally excited HF

    E-Print Network [OSTI]

    Yang, Benhui; Forrey, R C; Stancil, P C; Balakrishnan, N

    2015-01-01T23:59:59.000Z

    Collisional excitation rate coefficients play an important role in the dynamics of energy transfer in the interstellar medium. In particular, accurate rotational excitation rates are needed to interpret microwave and infrared observations of the interstellar gas for nonlocal thermodynamic equilibrium line formation. Theoretical cross sections and rate coefficients for collisional deexcitation of rotationally excited HF in the vibrational ground state are reported. The quantum-mechanical close-coupling approach implemented in the nonreactive scattering code MOLSCAT was applied in the cross section and rate coefficient calculations on an accurate 2D HF-He potential energy surface. Estimates of rate coefficients for H and H$_2$ colliders were obtained from the HF-He collisional data with a reduced-potential scaling approach. The calculation of state-to-state rotational quenching cross sections for HF due to He with initial rotational levels up to $j=20$ were performed for kinetic energies from 10$^{-5}$ to 15000...

  6. Galactic Rotation and Large Scale Structures

    E-Print Network [OSTI]

    B. G. Sidharth

    1999-04-05T23:59:59.000Z

    On the basis of a recent cosmological model, the puzzle of galactic rotational velocities at their edges is explained without invoking dark matter. A rationale for the existence of structures like galaxies and superclusters is also obtained.

  7. ROTATIONAL DOPPLER BEAMING IN ECLIPSING BINARIES

    SciTech Connect (OSTI)

    Groot, Paul J., E-mail: pgroot@astro.ru.nl [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2012-01-20T23:59:59.000Z

    In eclipsing binaries the stellar rotation of the two components will cause a rotational Doppler beaming during eclipse ingress and egress when only part of the eclipsed component is covered. For eclipsing binaries with fast spinning components this photometric analog of the well-known spectroscopic Rossiter-McLaughlin effect can exceed the strength of the orbital effect. Example light curves are shown for a detached double white dwarf binary, a massive O-star binary and a transiting exoplanet case, similar to WASP-33b. Inclusion of the rotational Doppler beaming in eclipsing systems is a prerequisite for deriving the correct stellar parameters from fitting high-quality photometric light curves and can be used to determine stellar obliquities as well as, e.g., an independent measure of the rotational velocity in those systems that may be expected to be fully synchronized.

  8. Consider Steam Turbine Drives for Rotating Equipment

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This revised ITP tip sheet on steam turbine drives for rotating equipment provides how-to advice for improving the system using low-cost, proven practices and technologies.

  9. Hydrogen atom in rotationally invariant noncommutative space

    E-Print Network [OSTI]

    Kh. P. Gnatenko; V. M. Tkachuk

    2014-11-03T23:59:59.000Z

    We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

  10. Rotation in an exact hydro model

    E-Print Network [OSTI]

    Csernai, L P; Csorgo, T

    2014-01-01T23:59:59.000Z

    We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

  11. Rotation in an exact hydro model

    E-Print Network [OSTI]

    L. P. Csernai; D. J. Wang; T. Csorgo

    2014-07-07T23:59:59.000Z

    We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

  12. Wavelet Analysis of Galactic Rotation Curves

    E-Print Network [OSTI]

    M. Kuassivi

    2011-04-28T23:59:59.000Z

    The spatial wavelet spectra of 73 published spiral galaxies's rotation curves are computed and their associated scaleograms are presented. Scaleograms are used to detect and isolate local features observed in spiral galaxies's rotation curves. Although wiggles and bumps are usually interpreted as signs of recent and on-going merging, the analysis of the scaleograms reveals regular patterns consistent with the presence of large-scale modes throughout the disk.

  13. Spin Rotation of Formalism for Spin Tracking

    SciTech Connect (OSTI)

    Luccio,A.

    2008-02-01T23:59:59.000Z

    The problem of which coefficients are adequate to correctly represent the spin rotation in vector spin tracking for polarized proton and deuteron beams in synchrotrons is here re-examined in the light of recent discussions. The main aim of this note is to show where some previous erroneous results originated and how to code spin rotation in a tracking code. Some analysis of a recent experiment is presented that confirm the correctness of the assumptions.

  14. Critical frequency in nuclear chiral rotation

    E-Print Network [OSTI]

    P. Olbratowski; J. Dobaczewski; J. Dudek

    2002-11-25T23:59:59.000Z

    Within the cranked Skyrme-Hartree-Fock approach the self-consistent solutions have been obtained for planar and chiral rotational bands in 132La. It turns out that the chiral band cannot exist below some critical rotational frequency which in the present case equals omega=0.6MeV. The appearance of the critical frequency is explained in terms of a simple classical model of two gyroscopes coupled to a triaxial rigid body.

  15. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY)

    2000-08-29T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

  16. AIAA 20023642 Effect of Rotation on Flow in a

    E-Print Network [OSTI]

    Jacob, Jamey

    AIAA 2002­3642 Effect of Rotation on Flow in a Ribbed Rotating Turbine Blade Cooling Duct Model Propulsion Conference AIAA-2002-3642 Effect of Rotation on Flow in a Ribbed Rotating Turbine Blade Cooling experiments in turbine blade cooling have fo- cused primarily on both simple and complex channel flow

  17. Control of molecular rotation in the limit of extreme rotational excitation

    E-Print Network [OSTI]

    V. Milner; J. W. Hepburn

    2015-01-12T23:59:59.000Z

    Laser control of molecular rotation is an area of active research. A number of recent studies has aimed at expanding the reach of rotational control to extreme, previously inaccessible rotational states, as well as controlling the directionality of molecular rotation. Dense ensembles of molecules undergoing ultrafast uni-directional rotation, known as molecular superrotors, are anticipated to exhibit unique properties, from spatially anisotropic diffusion and vortex formation to the creation of powerful acoustic waves and tuneable THz radiation. Here we describe our recent progress in controlling molecular rotation in the regime of high rotational excitation. We review two experimental techniques of producing uni-directional rotational wave packets with a "chiral train" of femtosecond pulses and an "optical centrifuge". Three complementary detection methods, enabling the direct observation, characterization and control of the superrotor states, are outlined: the one based on coherent Raman scattering, and two other methods employing both resonant and non-resonant multi-photon ionization. The capabilities of the described excitation and detection techniques are demonstrated with a few examples. The paper is concluded with an outlook for future developments.

  18. Heart - Shaped Nuclei: Condensation of Rotational Aligned Octupole Phonons

    E-Print Network [OSTI]

    S. Frauendorf

    2007-10-24T23:59:59.000Z

    The strong octupole correlations in the mass region $A\\approx 226$ are interpreted as rotation-induced condensation of octupole phonons having their angular momentum aligned with the rotational axis. Discrete phonon energy and parity conservation generate oscillations of the energy difference between the lowest rotational bands with positive and negative parity. Anharmonicities tend to synchronize the the rotation of the condensate and the quadrupole shape of the nucleus forming a rotating heart shape.

  19. Position, rotation, and intensity invariant recognizing method

    DOE Patents [OSTI]

    Ochoa, Ellen (Pleasanton, CA); Schils, George F. (San Ramon, CA); Sweeney, Donald W. (Alamo, CA)

    1989-01-01T23:59:59.000Z

    A method for recognizing the presence of a particular target in a field of view which is target position, rotation, and intensity invariant includes the preparing of a target-specific invariant filter from a combination of all eigen-modes of a pattern of the particular target. Coherent radiation from the field of view is then imaged into an optical correlator in which the invariant filter is located. The invariant filter is rotated in the frequency plane of the optical correlator in order to produce a constant-amplitude rotational response in a correlation output plane when the particular target is present in the field of view. Any constant response is thus detected in the output The U.S. Government has rights in this invention pursuant to Contract No. DE-AC04-76DP00789 between the U.S. Department of Energy and AT&T Technologies, Inc.

  20. Controlling inertial focussing using rotational motion

    E-Print Network [OSTI]

    Prohm, Christopher; Stark, Holger

    2014-01-01T23:59:59.000Z

    In inertial microfluidics lift forces cause a particle to migrate across streamlines to specific positions in the cross section of a microchannel. We control the rotational motion of a particle and demonstrate that this allows to manipulate the lift-force profile and thereby the particle's equilibrium positions. We perform two-dimensional simulation studies using the method of multi-particle collision dynamics. Particles with unconstrained rotational motion occupy stable equilibrium positions in both halfs of the channel while the center is unstable. When an external torque is applied to the particle, two equilibrium positions annihilate by passing a saddle-node bifurcation and only one stable fixpoint remains so that all particles move to one side of the channel. In contrast, non-rotating particles accumulate in the center and are pushed into one half of the channel when the angular velocity is fixed to a non-zero value.

  1. Measuring deflections in a rotating shaft

    E-Print Network [OSTI]

    Bailey, Edmond Ira

    1968-01-01T23:59:59.000Z

    . Short range telemetry (4, 5) involves placing a frequency modulated transmitter on the rotating member and locating a receiver in close proximity such that the data may be trans fered from the rotat1ng member to the stationary readout. l Numbers... was insignificant. The above is the situation for which the measuring system was to be disigned. The accuracy desired for the measuring system was speci fied as + 5L' by Mr. Alexander (6) as needed for his research. The approximate critical speed of the shaft...

  2. Vacuum coupling of rotating superconducting rotor

    DOE Patents [OSTI]

    Shoykhet, Boris A.; Zhang, Burt Xudong; Driscoll, David Infante

    2003-12-02T23:59:59.000Z

    A rotating coupling allows a vacuum chamber in the rotor of a superconducting electric motor to be continually pumped out. The coupling consists of at least two concentric portions, one of which is allowed to rotate and the other of which is stationary. The coupling is located on the non-drive end of the rotor and is connected to a coolant supply and a vacuum pump. The coupling is smaller in diameter than the shaft of the rotor so that the shaft can be increased in diameter without having to increase the size of the vacuum seal.

  3. A theoretical analysis of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y.; Kamijo, K. (National Aerospace Lab., Miyagi, (Japan)); Yoshida, Y. (Osaka Univ., Toyonaka, (Japan). Engineering Science)

    1993-03-01T23:59:59.000Z

    Rotating cavitation was analyzed using an actuator disk method. Quasi-steady pressure performance of the impeller, mass flow gain factor, and cavitation compliance of the cavity were taken into account. Three types of destabilizing modes were predicted: rotation cavitation propagating faster than the rotational speed of the impeller, rotating cavitation propagating in the direction opposite that of the impeller, and rotating stall propagating slower than the rotational speed of the impeller. It was shown that both types of rotating cavitation were caused by the positive mass flow gain factor, while the rotating stall was caused by the positive slope of the pressure performance. Stability and propagation velocity maps are presented for the two types of rotating cavitation in the mass flow gain factor-cavitation compliance place. The correlation between theoretical results and experimental observations is discussed.

  4. (Revised May 22, 2012) Rotational Dynamics (Energy)

    E-Print Network [OSTI]

    Collins, Gary S.

    energy (the sum of kinetic and potential energies) to derive an expression for the moment of inertia that the expression for kinetic energy takes on this simple form. Experiment Set Up The apparatus consists of a Rotary. The rotating object has kinetic energy but we cannot write it in the familiar form ½mv2 because the velocities

  5. STEPS IN SLOW FLAGELLAR MOTOR ROTATION

    E-Print Network [OSTI]

    Leake, Mark C.

    STEPS IN SLOW FLAGELLAR MOTOR ROTATION Alexander D. Rowe1 , Yoshiyuki Sowa2, Mark C. Leake1+ -specific motors. Torque is generated by the interaction between stator complexes and FliG proteins revolution. CHIMERIC MOTOR: The stator units comprising the flagellar motors of the YS34 strain - used

  6. Wave-particle Interactions In Rotating Mirrors

    SciTech Connect (OSTI)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2011-01-11T23:59:59.000Z

    Wave-particle interactions in E×B rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy. This wave-particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas, the alpha particles may be removed at low energy through the loss cone, and the energy lost may be transferred to the radial electric field. This eliminates the need for electrodes in the mirror throat, which have presented serious technical issues in past rotating plasma devices. A particularly simple way to achieve this effect is to use a high azimuthal mode number perturbation on the magnetic field. Rotation can also be sustained by waves in plasmas without a kinetic energy source. This type of wave has been considered for plasma centrifuges used for isotope separation. Energy may also be transferred from the electric field to particles or waves, which may be useful for ion heating and energy generation.

  7. Rotatable superconducting cyclotron adapted for medical use

    DOE Patents [OSTI]

    Blosser, Henry G. (East Lansing, MI); Johnson, David A. (Williamston, MI); Riedel, Jack (East Lansing, MI); Burleigh, Richard J. (Berkeley, CA)

    1985-01-01T23:59:59.000Z

    A superconducting cyclotron (10) rotatable on a support structure (11) in an arc of about 180.degree. around a pivot axis (A--A) and particularly adapted for medical use is described. The rotatable support structure (13, 15) is balanced by being counterweighted (14) so as to allow rotation of the cyclotron and a beam (12), such as a subparticle (neutron) or atomic particle beam, from the cyclotron in the arc around a patient. Flexible hose (25) is moveably attached to the support structure for providing a liquified gas which is supercooled to near 0.degree. K. to an inlet means (122) to a chamber (105) around superconducting coils (101, 102). The liquid (34) level in the cyclotron is maintained approximately half full so that rotation of the support structure and cyclotron through the 180.degree. can be accomplished without spilling the liquid from the cyclotron. With the coils vertically oriented, each turn of the winding is approximately half immersed in liquid (34) and half exposed to cold gas and adequate cooling to maintain superconducting temperatures in the section of coil above the liquid level is provided by the combination of cold gas/vapor and by the conductive flow of heat along each turn of the winding from the half above the liquid to the half below.

  8. Solar Dynamics, Rotation, Convection and Overshoot

    E-Print Network [OSTI]

    Hanasoge, S; Roth, M; Schou, J; Schuessler, M; Thompson, M J

    2015-01-01T23:59:59.000Z

    We discuss recent observational, theoretical and modeling progress made in understanding the Sun's internal dynamics, including its rotation, meridional flow, convection and overshoot. Over the past few decades, substantial theoretical and observational effort has gone into appreciating these aspects of solar dynamics. A review of these observations, related helioseismic methodology and inference and computational results in relation to these problems is undertaken here.

  9. Lateral displacement and rotational displacement sensor

    DOE Patents [OSTI]

    Duden, Thomas

    2014-04-22T23:59:59.000Z

    A position measuring sensor formed from opposing sets of capacitor plates measures both rotational displacement and lateral displacement from the changes in capacitances as overlapping areas of capacitors change. Capacitances are measured by a measuring circuit. The measured capacitances are provided to a calculating circuit that performs calculations to obtain angular and lateral displacement from the capacitances measured by the measuring circuit.

  10. On rigidly rotating perfect fluid cylinders

    E-Print Network [OSTI]

    B. V. Ivanov

    2002-05-07T23:59:59.000Z

    The gravitational field of a rigidly rotating perfect fluid cylinder with gamma- law equation of state is found analytically. The solution has two parameters and is physically realistic for gamma in the interval (1.41,2]. Closed timelike curves always appear at large distances.

  11. Rigidly rotating cylinders of charged dust

    E-Print Network [OSTI]

    B. V. Ivanov

    2002-07-02T23:59:59.000Z

    The gravitational field of a rigidly rotating cylinder of charged dust is found analytically. The general and all regular solutions are divided into three classes. The acceleration and the vorticity of the dust are given, as well as the conditions for the appearance of closed timelike curves.

  12. Spectroscopic observation of the rotational Doppler effect

    E-Print Network [OSTI]

    S. Barreiro; J. W. R. Tabosa; H. Failache; A. Lezama

    2006-07-26T23:59:59.000Z

    We report on the first spectroscopic observation of the rotational Doppler shift associated with light beams carrying orbital angular momentum. The effect is evidenced as the broadening of a Hanle/EIT coherence resonance on Rb vapor when the two incident Laguerre-Gaussian laser beams have opposite topological charges. The observations closely agree with theoretical predictions.

  13. Observation of Bloch oscillations in molecular rotation

    E-Print Network [OSTI]

    Johannes Floß; Andrei Kamalov; Ilya Sh. Averbukh; Philip H. Bucksbaum

    2015-04-26T23:59:59.000Z

    The periodically kicked quantum rotor is known for non-classical effects such as quantum localisation in angular momentum space or quantum resonances in rotational excitation. These phenomena have been studied in diverse systems mimicking the kicked rotor, such as cold atoms in optical lattices, or coupled photonic structures. Recently, it was predicted that several solid state quantum localisation phenomena - Anderson localisation, Bloch oscillations, and Tamm-Shockley surface states - may manifest themselves in the rotational dynamics of laser-kicked molecules. Here, we report the first observation of rotational Bloch oscillations in a gas of nitrogen molecules kicked by a periodic train of femtosecond laser pulses. A controllable detuning from the quantum resonance creates an effective accelerating potential in angular momentum space, inducing Bloch-like oscillations of the rotational excitation. These oscillations are measured via the temporal modulation of the refractive index of the gas. Our results introduce room-temperature laser-kicked molecules as a new laboratory for studies of localisation phenomena in quantum transport.

  14. Excitation system for rotating synchronous machines

    DOE Patents [OSTI]

    Umans, Stephen D. (Belmont, MA); Driscoll, David J. (South Euclid, OH)

    2002-01-01T23:59:59.000Z

    A system for providing DC current to a rotating superconducting winding is provided. The system receives current feedback from the superconducting winding and determines an error signal based on the current feedback and a reference signal. The system determines a control signal corresponding to the error signal and provides a positive and negative superconducting winding excitation voltage based on the control signal.

  15. Quantum Vacuum Instability Near Rotating Stars

    E-Print Network [OSTI]

    A L Matacz; A C Ottewill; P C W Davies

    1992-12-08T23:59:59.000Z

    We discuss the Starobinskii-Unruh process for the Kerr black hole. We show how this effect is related to the theory of squeezed states. We then consider a simple model for a highly relativistic rotating star and show that the Starobinskii-Unruh effect is absent.

  16. Convective heat transfer in rotating, circular channels

    E-Print Network [OSTI]

    Hogan, Brenna Elizabeth

    2012-01-01T23:59:59.000Z

    Nusselt number values for flow in a rotating reference frame are obtained through computational fluid dynamic (CFD) analysis for Rossby numbers Ro ~1-4 and Reynolds numbers Re ~1,000-2,000. The heat-transfer model is first ...

  17. Three-dimensional rotating stall inception and effects of rotating tip clearance asymmetry in axial compressors

    E-Print Network [OSTI]

    Gordon, Kenneth A. (Kenneth Andrew), 1970-

    1999-01-01T23:59:59.000Z

    The effects of two types of flow nonuniformity on stall inception behavior were assessed with linearized stability analyses of two compressor flow models. Response to rotating tip clearance asymmetries induced by a whirling ...

  18. Film cooling effectiveness measurements on rotating and non-rotating turbine components

    E-Print Network [OSTI]

    Ahn, Jaeyong

    2007-04-25T23:59:59.000Z

    have significant effects on surface static pressure and film-cooling effectiveness. Same technique was applied to the rotating turbine blade leading edge region. Tests were conducted on the first stage rotor of a 3-stage axial turbine. The Reynolds...

  19. Discreteness and resolution effects in rapidly rotating turbulence

    E-Print Network [OSTI]

    Bourouiba, Lydia

    Rotating turbulence is characterized by the nondimensional Rossby number Ro, which is a measure of the strength of the Coriolis term relative to that of the nonlinear term. For rapid rotation (Ro?0), nonlinear interactions ...

  20. Actuator assembly including a single axis of rotation locking member

    DOE Patents [OSTI]

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08T23:59:59.000Z

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  1. Three-dimensional simulation of a rotating supernova

    SciTech Connect (OSTI)

    Nakamura, K. [Faculty of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan); Kuroda, T. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Takiwaki, T. [Center for Computational Astrophysics, National Astronomical Observatory of Japan, Osawa 2-21-1, Mitaka, Tokyo 181-8588 (Japan); Kotake, K. [Department of Applied Physics, Fukuoka University, Jonan, Fukuoka 814-0180 (Japan)

    2014-05-02T23:59:59.000Z

    We investigate the effects of rotation on the evolution of core-collapse supernova explosion using a 15 solar mass progenitor model with a variety of neutrino luminosity and rotational velocity. Stars should have some amount of angular momentum, which would affect stellar evolution and its final explosion. In this paper we focus on the effect of rotation on gravitational collapse of a core, on a core bounce of accreting matter, and on subsequent generation and evolution of a shock wave. We find that the rotation plays a positive role for supernova explosions. More rapidly rotating models present more rapid expansion of the shock front and more energetic explosions. When the rotational speed is moderate, the shock once stalls at about 200 km away from the center similarly to a non-rotating model. Then the rotating progenitor experiences effective neutrino heating especially around an equatorial plane and explodes even with somewhat low neutrino luminosity for which the non-rotating model cannot overcome accreting matter and finally collapses. When the rotational speed is fast, the shock expands to about 300 km immediately after the core bounce and then evolves to move outward without shock stalling. We conclude that this positive effect of rotation to explosions is dominant against some possible negative aspects, for example, lower neutrino luminosity caused by less contraction of the rotating core.

  2. Steady periodic waves bifurcating for fixed-depth rotational flows

    E-Print Network [OSTI]

    consider steady periodic water waves for rotational flows with a specified fixed-depth over a flat bed. We the existence of steady periodic water waves for rotational flows with a specified fixed depth over a flat bedSteady periodic waves bifurcating for fixed-depth rotational flows David Henry School

  3. Counter-rotating Kerr manifolds separated by a fluid shell

    E-Print Network [OSTI]

    J. P. Krisch; E. N. Glass

    2009-08-13T23:59:59.000Z

    We describe a spheroidal fluid shell between two Kerr vacuum regions which have opposite rotation parameters. The shell has a stiff equation of state and a heat flow vector related to the rotational Killing current. The shell description is useful in exploring the significance of counter-rotation in Kerr metric matches.

  4. Modeling and Control of Surge and Rotating Stall in Compressors

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    Modeling and Control of Surge and Rotating Stall in Compressors Dr.ing. thesis Jan Tommy Gravdahl of rotating stall and surge in compressors. A close coupled valve is included in the Moore­constant compressor speed is derived by extending the Moore­Greitzer model. Rotating stall and surge is studied

  5. Modeling and Control of Surge and Rotating Stall in Compressors

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    Modeling and Control of Surge and Rotating Stall in Compressors Dr.ing. thesis Jan Tommy Gravdahl of rotating stall and surge in compressors. A close coupled valve is included in the Moore-constant compressor speed is derived by extending the Moore-Greitzer model. Rotating stall and surge is studied

  6. Generalization of rotational mechanics and application to aerospace systems

    E-Print Network [OSTI]

    Sinclair, Andrew James

    2005-08-29T23:59:59.000Z

    -dimensions and the derivative of the principal-rotation parameters. A new minimum-parameter description of N-dimensional orientation is directly related to the principal-rotation parameters. The mapping of arbitrary dynamical systems into N-dimensional rotations and the merits...

  7. INVITED PAPERS Transport and sawtooth oscillations from rotational pumping

    E-Print Network [OSTI]

    California at San Diego, University of

    INVITED PAPERS Transport and sawtooth oscillations from rotational pumping of a magnetized electron measurements have been made of cross-field transport from ``rotational pumping'' of a magnetized electron column. Rotational pumping is the collisional dissipation of the axial compressions that are caused by E

  8. A Novel Membrane Finite Element with Drilling Rotations

    E-Print Network [OSTI]

    Kouhia, Reijo

    A Novel Membrane Finite Element with Drilling Rotations Reijo Kouhia 1 Abstract. A new low order interpolation is used for the drill rotation #12;eld. Both triangular and quadrilateral elements are considered of freedom. 1 INTRODUCTION In-plane rotational degrees of freedom, \\drilling de- grees of freedom

  9. Chiral meta-atoms rotated by light

    SciTech Connect (OSTI)

    Liu Mingkai; Powell, David A.; Shadrivov, Ilya V. [Nonlinear Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2012-07-16T23:59:59.000Z

    We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

  10. Quantum Mechanics of a Rotating Billiard

    E-Print Network [OSTI]

    Nandan Jha; Sudhir R. Jain

    2014-06-12T23:59:59.000Z

    Integrability of a square billiard is spontaneously broken as it rotates about one of its corners. The system becomes quasi-integrable where the invariant tori are broken with respect to a certain parameter, $\\lambda = 2E/\\omega^{2}$ where E is the energy of the particle inside the billiard and $\\omega$ is the angular frequency of rotation of billiard. We study the system classically and quantum mechanically in view of obtaining a correspondence in the two descriptions. Classical phase space in Poincar\\'{e} surface of section shows transition from regular to chaotic motion as the parameter $\\lambda$ is decreased. In the Quantum counterpart, the spectral statistics shows a transition from Poisson to Wigner distribution as the system turns chaotic with decrease in $\\lambda$. The wavefunction statistics however show breakdown of time-reversal symmetry as $\\lambda$ decreases.

  11. Rotation and anisotropy of galaxies revisited

    E-Print Network [OSTI]

    James Binney

    2005-04-18T23:59:59.000Z

    The use of the tensor virial theorem (TVT) as a diagnostic of anisotropic velocity distributions in galaxies is revisited. The TVT provides a rigorous global link between velocity anisotropy, rotation and shape, but the quantities appearing in it are not easily estimated observationally. Traditionally use has been made of a centrally averaged velocity dispersion and the peak rotation velocity. Although this procedure cannot be rigorously justified, tests on model galaxies show that it works surprisingly well. With the advent of integral-field spectroscopy it is now possible to establish a rigorous connection between the TVT and observations. The TVT is reformulated in terms of sky-averages, and the new formulation is tested on model galaxies.

  12. Rotating sample holder at low temperature

    SciTech Connect (OSTI)

    Pasternak, Sebastien; Perrin, Florian; Ciatto, Gianluca; Palancher, Herve; Steinmann, Ricardo [European Synchrotron Radiation Facility, 38043 Grenoble (France)

    2007-07-15T23:59:59.000Z

    A low temperature rotary device (cryoturbine) for use in extended x-ray-absorption fine structure measurements in fluorescence mode has been designed and manufactured. The instrument works at a temperature close to liquid Nitrogen and can reach frequencies up to 100 Hz with good stability. The rotation speed is measured with a light-emitting diode driven in stroboscopic mode by a simple electronic circuit.

  13. Galaxy rotation curves in de Sitter space

    E-Print Network [OSTI]

    Maurice H. P. M. van Putten

    2015-01-27T23:59:59.000Z

    Dark energy inferred from the observed negative deceleration parameter introduces a small mass of the graviton, that satisfies the Higuchi stability condition. It implies an infra-red modification of gravitation that produces Milgrom's inverse distance law of gravitational attraction in excellent agreement with the observed galaxy rotation curves. We conclude that dark matter is present cosmologically with no need for local clustering in galaxies.

  14. Ghost condensate model of flat rotation curves

    E-Print Network [OSTI]

    V. V. Kiselev

    2005-07-29T23:59:59.000Z

    An effective action of ghost condensate with higher derivatives creates a source of gravity and mimics a dark matter in spiral galaxies. We present a spherically symmetric static solution of Einstein--Hilbert equations with the ghost condensate at large distances, where flat rotation curves are reproduced in leading order over small ratio of two energy scales characterizing constant temporal and spatial derivatives of ghost field: $\\mu_*^2$ and $\\mu_\\star^2$, respectively, with a hierarchy $\\mu_\\star\\ll \\mu_*$. We assume that a mechanism of hierarchy is provided by a global monopole in the center of galaxy. An estimate based on the solution and observed velocities of rotations in the asymptotic region of flatness, gives $\\mu_*\\sim 10^{19}$ GeV and the monopole scale in a GUT range $\\mu_\\star\\sim 10^{16}$ GeV, while a velocity of rotation $v_0$ is determined by the ratio: $ \\sqrt{2} v_0^2= \\mu_\\star^2/\\mu_*^2$. A critical acceleration is introduced and naturally evaluated of the order of Hubble rate, that represents the Milgrom's acceleration.

  15. Actomyosin contractility rotates the cell nucleus

    E-Print Network [OSTI]

    Abhishek Kumar; Ananyo Maitra; Madhuresh Sumit; Sriram Ramaswamy; G. V. Shivashankar

    2013-09-14T23:59:59.000Z

    The nucleus of the eukaryotic cell functions amidst active cytoskeletal filaments, but its response to the stresses carried by these filaments is largely unexplored. We report here the results of studies of the translational and rotational dynamics of the nuclei of single fibroblast cells, with the effects of cell migration suppressed by plating onto fibronectin-coated micro-fabricated patterns. Patterns of the same area but different shapes and/or aspect ratio were used to study the effect of cell geometry on the dynamics. On circles, squares and equilateral triangles, the nucleus undergoes persistent rotational motion, while on high-aspect-ratio rectangles of the same area it moves only back and forth. The circle and the triangle showed respectively the largest and the smallest angular speed. We show that our observations can be understood through a hydrodynamic approach in which the nucleus is treated as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and persistence time of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be a generic property that cells must balance by specific mechanisms in order to maintain nuclear homeostasis.

  16. Global empirical potentials from purely rotational measurements

    E-Print Network [OSTI]

    Dattani, Nikesh S; Sun, Ming; Johnson, Erin R; Roy, Robert J Le; Ziurys, Lucy M

    2014-01-01T23:59:59.000Z

    The recent advent of chirped-pulse FTMW technology has created a plethora of pure rotational spectra for molecules for which no vibrational information is known. The growing number of such spectra demands a way to build empirical potential energy surfaces for molecules, without relying on any vibrational measurements. Using ZnO as an example, we demonstrate a powerful technique for efficiently accomplishing this. We first measure eight new ultra-high precision ($\\pm2$ kHz) pure rotational transitions in the $X$-state of ZnO. Combining them with previous high-precision ($\\pm50$ kHz) pure rotational measurements of different transitions in the same system, we have data that spans the bottom 10\\% of the well. Despite not using any vibrational information, our empirical potentials are able to determine the size of the vibrational spacings and bond lengths, with precisions that are more than three and two orders of magnitude greater, respectively, than the most precise empirical values previously known, and the mo...

  17. Light curves from rapidly rotating neutron stars

    E-Print Network [OSTI]

    Numata, Kazutoshi

    2010-01-01T23:59:59.000Z

    We calculate light curves produced by a hot spot of a rapidly rotating neutron star, assuming that the spot is perturbed by a core $r$-mode, which is destabilized by emitting gravitational waves. To calculate light curves, we take account of relativistic effects such as the Doppler boost due to the rapid rotation and light bending assuming the Schwarzschild metric around the neutron star. We assume that the core $r$-modes penetrate to the surface fluid ocean to have sufficiently large amplitudes to disturb the spot. For a $l'=m$ core $r$-mode, the oscillation frequency $\\omega\\approx2m\\Omega/[l'(l'+1)]$ defined in the co-rotating frame of the star will be detected by a distant observer, where $l'$ and $m$ are respectively the spherical harmonic degree and the azimuthal wave number of the mode, and $\\Omega$ is the spin frequency of the star. In a linear theory of oscillation, using a parameter $A$ we parametrize the mode amplitudes such that ${\\rm max}\\left(|\\xi_\\theta|,|\\xi_\\phi|\\right)/R=A$ at the surface, w...

  18. Lithium depletion and the rotational history of exoplanet host stars

    E-Print Network [OSTI]

    Jerome Bouvier

    2008-09-03T23:59:59.000Z

    Israelian et al. (2004) reported that exoplanet host stars are lithium depleted compared to solar-type stars without detected massive planets, a result recently confirmed by Gonzalez (2008). We investigate whether enhanced lithium depletion in exoplanet host stars may result from their rotational history. We have developed rotational evolution models for slow and fast solar-type rotators from the pre-main sequence (PMS) to the age of the Sun and compare them to the distribution of rotational periods observed for solar-type stars between 1 Myr and 5 Gyr. We show that slow rotators develop a high degree of differential rotation between the radiative core and the convective envelope, while fast rotators evolve with little core-envelope decoupling. We suggest that strong differential rotation at the base of the convective envelope is responsible for enhanced lithium depletion in slow rotators. We conclude that lithium-depleted exoplanet host stars were slow rotators on the zero-age main sequence (ZAMS) and argue that slow rotation results from a long lasting star-disk interaction during the PMS. Altogether, this suggests that long-lived disks (> 5 Myr) may be a necessary condition for massive planet formation/migration.

  19. Double-Couple Earthquake Source: Symmetry and Rotation

    E-Print Network [OSTI]

    Kagan, Yan Y

    2012-01-01T23:59:59.000Z

    We consider statistical analysis of double couple (DC) earthquake focal mechanism orientation. The symmetry of DC changes with its geometrical properties, and the number of 3-D rotations one DC source can be transformed into another depends on its symmetry. Four rotations exist in a general case of DC with the nodal-plane ambiguity, two transformations if the fault plane is known, and one rotation if the sides of the fault plane are known. The symmetry of rotated objects is extensively analyzed in statistical material texture studies, and we apply their results to analyzing DC orientation. We consider theoretical probability distributions which can be used to approximate observational patterns of focal mechanisms. Uniform random rotation distributions for various DC sources are discussed, as well as two non-uniform distributions: the rotational Cauchy and von Mises-Fisher. We discuss how parameters of these rotations can be estimated by a statistical analysis of earthquake source properties in global seismici...

  20. Isorotation and differential rotation in a magnetic mirror with imposed E Multiplication-Sign B rotation

    SciTech Connect (OSTI)

    Romero-Talamas, C. A.; Elton, R. C.; Young, W. C.; Reid, R.; Ellis, R. F. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)

    2012-07-15T23:59:59.000Z

    Doppler spectroscopy of helium impurities in the Maryland Centrifugal Experiment reveals the simultaneous existence of isorotating and differentially rotating magnetic surfaces. Differential rotation occurs at the innermost surfaces and is conjectured to cause plasma voltage oscillations of hundreds of kilohertz by periodically changing the current path inductance. High-speed images show the periodic expulsion of plasma near the mirror ends at the same frequencies. In spite of this, the critical ionization velocity limit is exceeded, with respect to the vacuum field definition, for at least 0.5 ms.

  1. Relativistic theory of nuclear spin-rotation tensor with kinetically balanced rotational London orbitals

    SciTech Connect (OSTI)

    Xiao, Yunlong; Zhang, Yong; Liu, Wenjian, E-mail: liuwjbdf@gmail.com [Beijing National Laboratory for Molecular Sciences, Institute of Theoretical and Computational Chemistry, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, and Center for Computational Science and Engineering, Peking University, Beijing 100871 (China)

    2014-10-28T23:59:59.000Z

    Both kinetically balanced (KB) and kinetically unbalanced (KU) rotational London orbitals (RLO) are proposed to resolve the slow basis set convergence in relativistic calculations of nuclear spin-rotation (NSR) coupling tensors of molecules containing heavy elements [Y. Xiao and W. Liu, J. Chem. Phys. 138, 134104 (2013)]. While they perform rather similarly, the KB-RLO Ansatz is clearly preferred as it ensures the correct nonrelativistic limit even with a finite basis. Moreover, it gives rise to the same “direct relativistic mapping” between nuclear magnetic resonance shielding and NSR coupling tensors as that without using the London orbitals [Y. Xiao, Y. Zhang, and W. Liu, J. Chem. Theory Comput. 10, 600 (2014)].

  2. Rotations in the Space of Split Octonions

    E-Print Network [OSTI]

    Merab Gogberashvili

    2008-08-18T23:59:59.000Z

    The geometrical application of split octonions is considered. The modified Fano graphic, which represents products of the basis units of split octonionic, having David's Star shape, is presented. It is shown that active and passive transformations of coordinates in octonionic '8-space' are not equivalent. The group of passive transformations that leave invariant the norm of split octonions is SO(4,4), while active rotations is done by the direct product of O(3,4)-boosts and real non-compact form of the exceptional group $G_2$. In classical limit these transformations reduce to the standard Lorentz group.

  3. Rotating electric machine with fluid supported parts

    DOE Patents [OSTI]

    Smith, Jr., Joseph L. (Concord, MA); Kirtley, Jr., James L. (Brookline, MA)

    1981-01-01T23:59:59.000Z

    A rotating electric machine in which the armature winding thereof and other parts are supported by a liquid to withstand the mechanical stresses applied during transient overloads and the like. In particular, a narrow gap is provided between the armature winding and the stator which supports it and this gap is filled with an externally pressurized viscous liquid. The liquid is externally pressurized sufficiently to balance the static loads on the armature winding. Transient mechanical loads which deform the armature winding alter the gap dimensions and thereby additionally pressurize the viscous liquid to oppose the armature winding deformation and more nearly uniformly to distribute the resulting mechanical stresses.

  4. Mixing zones in magnetized differentially rotating stars

    E-Print Network [OSTI]

    V. Urpin

    2005-09-29T23:59:59.000Z

    We study the secular instability of magnetized differentially rotating radiative zones taking account of viscosity and magnetic and thermal diffusivities. The considered instability generalizes the well-known Goldreich-Schubert-Fricke instability for the case of a sufficiently strong magnetic field. In magnetized stars, instability can lead to a formation of non-spherical unstable zones where weak turbulence mixes the material between the surface and interiors. Such unstable zones can manifest themselves by a non-spherical distribution of abundance anormalies on the stellar surface.

  5. Collisional Penrose Process in Rotating Wormhole Spacetime

    E-Print Network [OSTI]

    Tsukamoto, Naoki

    2015-01-01T23:59:59.000Z

    In a collisional Penrose process, two particles coming from the asymptotically flat region collide in the ergosphere of a compact object. The collision produces two new particles, one with positive energy and one with negative energy. When the particle with positive energy escapes to infinity, the process extracts energy from the compact object. In this paper, we study the collisional Penrose process in a rotating wormhole spacetime. We consider the simple case of a head-on collision at the throat of a Teo wormhole. We find that the process of energy extraction from a Teo wormhole can be substantially more efficient than the collisional Penrose process in the Kerr black hole spacetime.

  6. Collisional Penrose Process in Rotating Wormhole Spacetime

    E-Print Network [OSTI]

    Naoki Tsukamoto; Cosimo Bambi

    2015-05-29T23:59:59.000Z

    In a collisional Penrose process, two particles coming from the asymptotically flat region collide in the ergosphere of a compact object. The collision produces two new particles, one with positive energy and one with negative energy. When the particle with positive energy escapes to infinity, the process extracts energy from the compact object. In this paper, we study the collisional Penrose process in a rotating wormhole spacetime. We consider the simple case of a head-on collision at the throat of a Teo wormhole. We find that the process of energy extraction from a Teo wormhole can be substantially more efficient than the collisional Penrose process in the Kerr black hole spacetime.

  7. Algebraically general, gravito-electric rotating dust

    E-Print Network [OSTI]

    Lode Wylleman

    2008-06-17T23:59:59.000Z

    The class of gravito-electric, algebraically general, rotating `silent' dust space-times is studied. The main invariant properties are deduced. The number $t_0$ of functionally independent zero-order Riemann invariants satisfies $1\\leq t_0\\leq 2$ and special attention is given to the subclass $t_0=1$. Whereas there are no $\\Lambda$-term limits comprised in the class, the limit for vanishing vorticity leads to two previously derived irrotational dust families with $\\Lambda>0$, and the shear-free limit is the G\\"{o}del universe.

  8. More on Rotations as Spin Matrix Polynomials

    E-Print Network [OSTI]

    Thomas L. Curtright

    2015-07-11T23:59:59.000Z

    Any nonsingular function of spin j matrices always reduces to a matrix polynomial of order 2j. The challenge is to find a convenient form for the coefficients of the matrix polynomial. The theory of biorthogonal systems is a useful framework to meet this challenge. Central factorial numbers play a key role in the theoretical development. Explicit polynomial coefficients for rotations expressed either as exponentials or as rational Cayley transforms are considered here. Structural features of the results are discussed and compared, and large j limits of the coefficients are examined.

  9. Collisional Penrose Process in Rotating Wormhole Spacetime

    E-Print Network [OSTI]

    Naoki Tsukamoto; Cosimo Bambi

    2015-03-22T23:59:59.000Z

    In a collisional Penrose process, two particles coming from the asymptotically flat region collide in the ergosphere of a compact object. The collision produces two new particles, one with positive energy and one with negative energy. When the particle with positive energy escapes to infinity, the process extracts energy from the compact object. In this paper, we study the collisional Penrose process in a rotating wormhole spacetime. We consider the simple case of a head-on collision at the throat of a Teo wormhole. We find that the process of energy extraction from a Teo wormhole can be substantially more efficient than the collisional Penrose process in the Kerr black hole spacetime.

  10. Wigner density of a rigid rotator

    SciTech Connect (OSTI)

    Malta, C.P. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo (Brazil)] [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo (Brazil); Marshall, T.S. [Department of Mathematics, University of Manchester, Manchester M139PL (United Kingdom)] [Department of Mathematics, University of Manchester, Manchester M139PL (United Kingdom); Santos, E. [Departamento de Fisica Moderna, Universidad de Cantabria, 39005, Santander (Spain)] [Departamento de Fisica Moderna, Universidad de Cantabria, 39005, Santander (Spain)

    1997-03-01T23:59:59.000Z

    We show that the Wigner density of the rigid rotator, in an appropriate, i.e., four-dimensional, phase space, is positive. This result holds in the ground state (S state), and also in the thermal mixture state at all finite temperatures. We discuss the implications of our result for the description of angular momentum in quantum mechanics; in particular, we reexamine, in the light of this new evidence, the suggestion made by Einstein and Stern [Ann. Phys. {bold 40}, 551 (1913)] that there is a nontrivial distribution of angular momentum in the S state. {copyright} {ital 1997} {ital The American Physical Society}

  11. Advanced Rotating Heat Exchangers | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'s Reply Comments AT&T,FACT S HEET FACT S HEET FACT S HEET|Rotating Heat

  12. Hidden Rotational Symmetries in Magnetic Domain Patterns

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment ofHeatHenryDuncan -Hidden Rotational

  13. Hidden Rotational Symmetries in Magnetic Domain Patterns

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment ofHeatHenryDuncan -Hidden RotationalHidden

  14. Hidden Rotational Symmetries in Magnetic Domain Patterns

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanfordDepartment ofHeatHenryDuncan -HiddenHidden Rotational

  15. Electromagnetic counterparts from counter-rotating relativistic kicked discs

    E-Print Network [OSTI]

    Olindo Zanotti

    2011-08-23T23:59:59.000Z

    We show the results of two dimensional general relativistic inviscid and isothermal hydrodynamical simulations comparing the behavior of co-rotating (with respect to the black hole rotation) and counter-rotating circumbinary quasi-Keplerian discs in the post merger phase of a supermassive binary black hole system. While confirming the spiral shock generation within the disc due to the combined effects of mass loss and recoil velocity of the black hole, we find that the maximum luminosity of counter-rotating discs is a factor ~(2-12) higher than in the co-rotating case, depending on the spin of the black hole. On the other hand, the luminosity peak happens ~10 days later with respect to the co-rotating case, for a binary with a total mass M~10^6 M_\\odot. Although the global dynamics of counter-rotating discs in the post merger phase of a merging event is very similar to that for co-rotating discs, an important difference has been found. In fact, increasing the spin of the central black hole produces more luminous co-rotating discs while less luminous counter-rotating ones.

  16. Dynamics and Statistical Mechanics of Rotating and non-Rotating Vortical Flows

    SciTech Connect (OSTI)

    Lim, Chjan [RPI] [RPI

    2013-12-18T23:59:59.000Z

    Three projects were analyzed with the overall aim of developing a computational/analytical model for estimating values of the energy, angular momentum, enstrophy and total variation of fluid height at phase transitions between disordered and self-organized flow states in planetary atmospheres. It is believed that these transitions in equilibrium statistical mechanics models play a role in the construction of large-scale, stable structures including super-rotation in the Venusian atmosphere and the formation of the Great Red Spot on Jupiter. Exact solutions of the spherical energy-enstrophy models for rotating planetary atmospheres by Kac's method of steepest descent predicted phase transitions to super-rotating solid-body flows at high energy to enstrophy ratio for all planetary spins and to sub-rotating modes if the planetary spin is large enough. These canonical statistical ensembles are well-defined for the long-range energy interactions that arise from 2D fluid flows on compact oriented manifolds such as the surface of the sphere and torus. This is because in Fourier space available through Hodge theory, the energy terms are exactly diagonalizable and hence has zero range, leading to well-defined heat baths.

  17. Atmos. Meas. Tech., 3, 13331349, 2010 www.atmos-meas-tech.net/3/1333/2010/

    E-Print Network [OSTI]

    of Energy (DOE) Atmospheric Ra- diation Measurement (ARM) Southern Great Plains site. A detailed case study-filter Rotating Shadowband Radiometers (MFRSRs). The interpolation algorithm that is used to project MFRSR point measurements onto the air- craft flight tracks is tested using AOD derived from NASA Langley High Spectral

  18. Faraday rotation: effect of magnetic field reversals

    E-Print Network [OSTI]

    Melrose, D B

    2010-01-01T23:59:59.000Z

    The standard formula for the rotation measure, RM, which determines the position angle, $\\psi={\\rm RM}\\lambda^2$, due to Faraday rotation, includes contributions only from the portions of the ray path where the natural modes of the plasma are circularly polarized. In small regions of the ray path where the projection of the magnetic field on the ray path reverses sign (called QT regions) the modes are nearly linearly polarized. The neglect of QT regions in estimating RM is not well justified at frequencies below a transition frequency where mode coupling changes from strong to weak. By integrating the polarization transfer equation across a QT region in the latter limit, I estimate the additional contribution $\\Delta\\psi$ needed to correct this omission. In contrast with a result proposed by \\cite{BB10}, $\\Delta\\psi$ is small and probably unobservable. I identify a new source of circular polarization, due to mode coupling in an asymmetric QT region. I also identify a new circular-polarization-dependent correc...

  19. FARADAY ROTATION: EFFECT OF MAGNETIC FIELD REVERSALS

    SciTech Connect (OSTI)

    Melrose, D. B. [SIfA, School of Physics, University of Sydney, NSW 2006 (Australia)

    2010-12-20T23:59:59.000Z

    The standard formula for the rotation measure (RM), which determines the position angle, {psi} = RM{lambda}{sup 2}, due to Faraday rotation, includes contributions only from the portions of the ray path where the natural modes of the plasma are circularly polarized. In small regions of the ray path where the projection of the magnetic field on the ray path reverses sign (called QT regions) the modes are nearly linearly polarized. The neglect of QT regions in estimating RM is not well justified at frequencies below a transition frequency where mode coupling changes from strong to weak. By integrating the polarization transfer equation across a QT region in the latter limit, I estimate the additional contribution {Delta}{psi} needed to correct this omission. In contrast with a result proposed by Broderick and Blandford, {Delta}{psi} is small and probably unobservable. I identify a new source of circular polarization, due to mode coupling in an asymmetric QT region. I also identify a new circular-polarization-dependent correction to the dispersion measure at low frequencies.

  20. Rotation Curve Measurement using Cross-Correlation

    E-Print Network [OSTI]

    Elizabeth J. Barton; Sheila J. Kannappan; Michael J. Kurtz; Margaret J. Geller

    2000-06-20T23:59:59.000Z

    Longslit spectroscopy is entering an era of increased spatial and spectral resolution and increased sample size. Improved instruments reveal complex velocity structure that cannot be described with a one-dimensional rotation curve, yet samples are too numerous to examine each galaxy in detail. Therefore, one goal of rotation curve measurement techniques is to flag cases in which the kinematic structure of the galaxy is more complex than a single-valued curve. We examine cross-correlation as a technique that is easily automated and works for low signal-to-noise spectra. We show that the technique yields well-defined errors which increase when the simple spectral model (template) is a poor match to the data, flagging those cases for later inspection. We compare the technique to the more traditional, parametric technique of simultaneous emission line fitting. When the line profile at a single slit position is non-Gaussian, the techniques disagree. For our model spectra with two well-separated velocity components, assigned velocities from the two techniques differ by up to ~52% of the velocity separation of the model components. However, careful use of the error statistics for either technique allows one to flag these non-Gaussian spectra.

  1. Test particle acceleration by rotating jet magnetospheres

    E-Print Network [OSTI]

    F. M. Rieger; K. Mannheim

    2000-11-01T23:59:59.000Z

    Centrifugal acceleration of charged test particles at the base of a rotating jet magnetosphere is considered. Based on an analysis of forces we derive the equation for the radial accelerated motion and present an analytical solution. It is shown that for particles moving outwards along rotating magnetic field lines, the energy gain is in particular limited by the breakdown of the bead-on-the-wire approximation which occurs in the vicinity of the light cylinder $r_{L}$. The corresponding upper limit for the maximum Lorentz factor $\\gamma_{max}$ for electrons scales $\\propto B^{2/3} r_{L}^{2/3}$, with $B$ the magnetic field strength at $r_{L}$, and is at most of the order of a $10^2-10^3$ for the conditions regarded to be typical for BL Lac objects. Such values suggest that this mechanism may provide pre-accelerated seed particles which are required for efficient Fermi-type particle acceleration at larger scales in radio jets.

  2. Actomyosin contractility rotates the cell nucleus

    E-Print Network [OSTI]

    Kumar, Abhishek; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

    2013-01-01T23:59:59.000Z

    The nucleus of the eukaryotic cell functions amidst active cytoskeletal filaments, but its response to the stresses carried by these filaments is largely unexplored. We report here the results of studies of the translational and rotational dynamics of the nuclei of single fibroblast cells, with the effects of cell migration suppressed by plating onto fibronectin-coated micro-fabricated patterns. Patterns of the same area but different shapes and/or aspect ratio were used to study the effect of cell geometry on the dynamics. On circles, squares and equilateral triangles, the nucleus undergoes persistent rotational motion, while on high-aspect-ratio rectangles of the same area it moves only back and forth. The circle and the triangle showed respectively the largest and the smallest angular speed. We show that our observations can be understood through a hydrodynamic approach in which the nucleus is treated as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active...

  3. Rotational actuator of motor based on carbon nanotubes

    DOE Patents [OSTI]

    Zettl, Alexander K. (Kensington, CA); Fennimore, Adam M. (Berkeley, CA); Yuzvinsky, Thomas D. (Berkeley, CA)

    2008-11-18T23:59:59.000Z

    A rotational actuator/motor based on rotation of a carbon nanotube is disclosed. The carbon nanotube is provided with a rotor plate attached to an outer wall, which moves relative to an inner wall of the nanotube. After deposit of a nanotube on a silicon chip substrate, the entire structure may be fabricated by lithography using selected techniques adapted from silicon manufacturing technology. The structures to be fabricated may comprise a multiwall carbon nanotube (MWNT), two in plane stators S1, S2 and a gate stator S3 buried beneath the substrate surface. The MWNT is suspended between two anchor pads and comprises a rotator attached to an outer wall and arranged to move in response to electromagnetic inputs. The substrate is etched away to allow the rotor to freely rotate. Rotation may be either in a reciprocal or fully rotatable manner.

  4. Laser induced rotation of trapped chiral and achiral nematic droplets

    E-Print Network [OSTI]

    Marjan Mosallaeipour; Yashodhan Hatwalne; N. V. Madhusudana; Sharath Ananthamurthy

    2010-02-05T23:59:59.000Z

    We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.

  5. Generation of Closed Timelike Curves with Rotating Superconductors

    E-Print Network [OSTI]

    Clovis Jacinto de Matos

    2007-01-19T23:59:59.000Z

    The spacetime metric around a rotating SuperConductive Ring (SCR) is deduced from the gravitomagnetic London moment in rotating superconductors. It is shown that theoretically it is possible to generate Closed Timelike Curves (CTC) with rotating SCRs. The possibility to use these CTC's to travel in time as initially idealized by G\\"{o}del is investigated. It is shown however, that from a technology and experimental point of view these ideas are impossible to implement in the present context.

  6. Alpha Channeling in Rotating Plasma with Stationary Waves

    SciTech Connect (OSTI)

    A. Fetterman and N.J. Fisch

    2010-02-15T23:59:59.000Z

    An extension of the alpha channeling effect to supersonically rotating mirrors shows that the rotation itself can be driven using alpha particle energy. Alpha channeling uses radiofrequency waves to remove alpha particles collisionlessly at low energy. We show that stationary magnetic fields with high n? can be used for this purpose, and simulations show that a large fraction of the alpha energy can be converted to rotation energy.

  7. Forming rotated SAR images by real-time motion compensation.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2012-12-01T23:59:59.000Z

    Proper waveform parameter selection allows collecting Synthetic Aperture Radar (SAR) phase history data on a rotated grid in the Fourier Space of the scene being imaged. Subsequent image formation preserves the rotated geometry to allow SAR images to be formed at arbitrary rotation angles without the use of computationally expensive interpolation or resampling operations. This should be useful where control of image orientation is desired such as generating squinted stripmaps and VideoSAR applications, among others.

  8. Study of vorticity in an exact rotating hydro model

    E-Print Network [OSTI]

    L. P. Csernai; J. H. Inderhaug

    2015-03-11T23:59:59.000Z

    We study a semianalytic exact solution of the fluid dynamical model of heavy ion reactions, and evaluate some observable signs of the rotation.

  9. Study of vorticity in an exact rotating hydro model

    E-Print Network [OSTI]

    Csernai, L P

    2015-01-01T23:59:59.000Z

    We study a semianalytic exact solution of the fluid dynamical model of heavy ion reactions, and evaluate some observable signs of the rotation.

  10. assisted rotational resonance: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    assist catheters. Using a simple test apparatus of a rotating densely packed bundle of hollow fiber membranes, water and blood gas exchange levels were Federspiel, William J. 24...

  11. INTERNAL-CYCLE VARIATION OF SOLAR DIFFERENTIAL ROTATION

    SciTech Connect (OSTI)

    Li, K. J.; Xie, J. L.; Shi, X. J., E-mail: lkj@ynao.ac.cn [National Astronomical Observatories/Yunnan Observatory, CAS, Kunming 650011 (China)

    2013-06-01T23:59:59.000Z

    The latitudinal distributions of the yearly mean rotation rates measured by Suzuki in 1998 and 2012 and Pulkkinen and Tuominen in 1998 are utilized to investigate internal-cycle variation of solar differential rotation. The rotation rate at the solar equator seems to have decreased since cycle 10 onward. The coefficient B of solar differential rotation, which represents the latitudinal gradient of rotation, is found to be smaller in the several years after the minimum of a solar cycle than in the several years after the maximum time of the cycle, and it peaks several years after the maximum time of the solar cycle. The internal-cycle variation of the solar rotation rates looks similar in profile to that of the coefficient B. A new explanation is proposed to address such a solar-cycle-related variation of the solar rotation rates. Weak magnetic fields may more effectively reflect differentiation at low latitudes with high rotation rates than at high latitudes with low rotation rates, and strong magnetic fields may more effectively repress differentiation at relatively low latitudes than at high latitudes. The internal-cycle variation is inferred as the result of both the latitudinal migration of the surface torsional pattern and the repression of strong magnetic activity in differentiation.

  12. arthroscopically repaired rotator: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when...

  13. arthroscopic rotator cuff: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when...

  14. Counter-Rotating Tandem Motor Drilling System

    SciTech Connect (OSTI)

    Kent Perry

    2009-04-30T23:59:59.000Z

    Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger than that of slim holes. As a result, the research team decided to complete the project, document the tested designs and seek further support for the concept outside of the DOE.

  15. Two-charged non-extremal rotating black holes in seven-dimensional gauged supergravity: The single-rotation case

    E-Print Network [OSTI]

    Shuang-Qing Wu

    2011-10-11T23:59:59.000Z

    We construct the solution for non-extremal charged rotating black holes in seven-dimensional gauged supergravity, in the case with only one rotation parameter and two independent charges. Using the Boyer-Lindquist coordinates, the metric is expressed in a generalized form of the ansatz previously presented in [S.Q. Wu, Phys. Rev. D 83 (2011) 121502(R)], which may be helpful to find the most general non-extremal two-charged rotating black hole with three unequal rotation parameters. The conserved charges for thermodynamics are also computed.

  16. Relativistic MHD Winds from Rotating Neutron Stars

    E-Print Network [OSTI]

    N. Bucciantini; T. A. Thompson; J. Arons; E. Quataert

    2006-12-22T23:59:59.000Z

    We solve the time-dependent dynamics of axisymmetric, general relativistic MHD winds from rotating neutron stars. The mass loss rate is obtained self consistently as a solution of the MHD equations, subject to a finite thermal pressure at the stellar surface. Conditions are chosen to be representative of the neutrino driven phase in newly born magnetars, which have been considered as a possible engine for GRBs. We compute the angular momentum and energy losses as a function of $\\sigma$ and compare them with the analytic expectation from the classical theory of pulsar winds. We observe the convergence to the force-free limit in the energy loss and we study the evolution of the closed zone for increasing magnetization. Results also show that the dipolar magnetic field and the presence of a closed zone do not modify significantly the acceleration and collimation properties of the wind.

  17. MULTI-DIMENSIONAL SIMULATIONS OF ROTATING PAIR-INSTABILITY SUPERNOVAE

    SciTech Connect (OSTI)

    Chatzopoulos, E.; Wheeler, J. Craig [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Couch, Sean M., E-mail: manolis@astro.as.utexas.edu [Department of Astronomy and Astrophysics, Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

    2013-10-20T23:59:59.000Z

    We study the effects of rotation on the dynamics, energetics, and {sup 56}Ni production of pair instability supernova (PISN) explosions by performing rotating two-dimensional ({sup 2}.5D{sup )} hydrodynamics simulations. We calculate the evolution of eight low-metallicity (Z = 10{sup –3}, 10{sup –4} Z{sub ?}) massive (135-245 M{sub ?}) PISN progenitors with initial surface rotational velocities of 50% of the critical Keplerian value using the stellar evolution code MESA. We allow for both the inclusion and the omission of the effects of magnetic fields in the angular momentum transport and in chemical mixing, resulting in slowly rotating and rapidly rotating final carbon-oxygen cores, respectively. Increased rotation for carbon-oxygen cores of the same mass and chemical stratification leads to less energetic PISN explosions that produce smaller amounts of {sup 56}Ni due to the effect of the angular momentum barrier that develops and slows the dynamical collapse. We find a non-monotonic dependence of {sup 56}Ni production on rotational velocity in situations when smoother composition gradients form at the outer edge of the rotating cores. In these cases, the PISN energetics are determined by the competition of two factors: the extent of chemical mixing in the outer layers of the core due to the effects of rotation in the progenitor evolution and the development of angular momentum support against collapse. Our 2.5D PISN simulations with rotation are the first presented in the literature. They reveal hydrodynamic instabilities in several regions of the exploding star and increased explosion asymmetries with higher core rotational velocity.

  18. Magnetic and antimagnetic rotation in covariant density functional theory

    SciTech Connect (OSTI)

    Zhao, P. W.; Liang, H. Z.; Peng, J.; Ring, P.; Zhang, S. Q.; Meng, J. [State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China); Department of Physics, Beijing Normal University, Beijing 100875 (China); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China) and Physik Department, Technische Universitat Muenchen, D-85747 Garching (Germany); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China); State Key Lab Nucl. Phys. and Tech., School of Physics, Peking University, Beijing 100871 (China) and Department of Physics, University of Stellenbosch, Stellenbosch (South Africa)

    2012-10-20T23:59:59.000Z

    Progress on microscopic and self-consistent description of the magnetic rotation and antimagnetic rotation phenomena in tilted axis cranking relativistic mean-field theory based on a point-coupling interaction are briefly reviewed. In particular, the microscopic pictures of the shears mechanism in {sup 60}Ni and the two shears-like mechanism in {sup 105}Cd are discussed.

  19. ROTATIONAL LEADERSHIP PROGRAM Grow strong leadership skillsin a

    E-Print Network [OSTI]

    Kaminsky, Werner

    ROTATIONAL LEADERSHIP PROGRAM #12;Grow strong leadership skillsin a one-of-a-kindFortune500. As an Evergreen, you'll be part of an 18-month leadership rotation at our Tacoma and Federal Way, Washington and mentor them to become a valuable part of our leadership succession plan. " Jim Hilger Chief Accounting

  20. Waveparticle interactions in rotating mirrorsa) Abraham J. Fettermanb)

    E-Print Network [OSTI]

    rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy. This wave­particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas

  1. Rotation as an origin of high energy particle collisions

    E-Print Network [OSTI]

    Zaslavskii, O B

    2015-01-01T23:59:59.000Z

    We consider collision of two particles in rotating spacetimes without horizons. If the metric coefficient responsible for rotation of spacetime is big enough in some region, the energy of collisions in the centre of mass frame can be as large as one likes. The results are model-independent and apply both to relativistic stars and wormholes.

  2. Differential rotation of the unstable nonlinear r-modes

    E-Print Network [OSTI]

    Friedman, John L; Lockitch, Keith H

    2015-01-01T23:59:59.000Z

    At second order in perturbation theory, the $r$-modes of uniformly rotating stars include an axisymmetric part that can be identified with differential rotation of the background star. If one does not include radiation-reaction, the differential rotation is constant in time and has been computed by S\\'a. It has a gauge dependence associated with the family of time-independent perturbations that add differential rotation to the unperturbed equilibrium star: For stars with a barotropic equation of state, one can add to the time-independent second-order solution arbitrary differential rotation that is stratified on cylinders (that is a function of distance $\\varpi$ to the axis of rotation). We show here that the gravitational radiation-reaction force that drives the $r$-mode instability removes this gauge freedom: The expontially growing differential rotation of the unstable second-order $r$-mode is unique. We derive a general expression for this rotation law for Newtonian models and evaluate it explicitly for s...

  3. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interactingInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. May 10, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP

  4. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    should be homogeneous within the condensate we prove by means of an asymptotic analysis in the stronglyInhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates M. Correggia , N. Rougerieb, France. September 19, 2012 Abstract We consider a 2D rotating Bose gas described by the Gross

  5. Selective Rotational Excitation of Molecular Isotopes and Nuclear Spin Isomers

    E-Print Network [OSTI]

    Sharly Fleischer; Ilya. Sh. Averbukh; Yehiam Prior

    2007-02-15T23:59:59.000Z

    Following excitation by a strong ultra-short laser pulse, molecules develop coordinated rotational motion, exhibiting transient alignment along the direction of the laser electric field, followed by periodic full and fractional revivals that depend on the molecular rotational constants. In mixtures, the different species undergo similar rotational dynamics, all starting together but evolving differently with each demonstrating its own periodic revival cycles. For a bimolecular mixture of linear molecules, at predetermined times, one species may attain a maximally aligned state while the other is anti-aligned (i.e. molecular axes are confined in a plane perpendicular to the laser electric field direction). By a properly timed second laser pulse, the rotational excitation of the undesired species may be almost completely removed leaving only the desired species to rotate and periodically realign, thus facilitating further selective manipulations by polarized light. In this paper, such double excitation schemes are demonstrated for mixtures of molecular isotopes (isotopologues) and for nuclear spin isomers.

  6. Semiclassical pair production rate for rotating electric fields

    E-Print Network [OSTI]

    Eckhard Strobel; She-Sheng Xue

    2015-02-09T23:59:59.000Z

    We semiclassically investigate Schwinger pair production for pulsed rotating electric fields depending on time. To do so we solve the Dirac equation for two-component fields in a WKB-like approximation. The result shows that for two-component fields the spin distribution of produced pairs is generally not $1:1$. As a result the pair creation rates of spinor and scalar quantum electro dynamics (QED) are different even for one pair of turning points. For rotating electric fields the pair creation rate is dominated by particles with a specific spin depending on the sense of rotation for a certain range of pulse lengths and frequencies. We present an analytical solution for the momentum spectrum of the constant rotating field. We find interference effects not only in the momentum spectrum but also in the total particle number of rotating electric fields.

  7. Rotational Doppler effect in x-ray photoionization

    SciTech Connect (OSTI)

    Sun Yuping; Wang Chuankui [College of Physics and Electronics, Shandong Normal University, 250014 Jinan (China); Theoretical Chemistry, Roslagstullsbacken 15, Royal Institute of Technology, S-106 91 Stockholm (Sweden); Gel'mukhanov, Faris [Theoretical Chemistry, Roslagstullsbacken 15, Royal Institute of Technology, S-106 91 Stockholm (Sweden)

    2010-11-15T23:59:59.000Z

    The energy of the photoelectron experiences a red or blue Doppler shift when the molecule recedes from the detector or approaches him. This results in a broadening of the photoelectron line due to the translational thermal motion. However, the molecules also have rotational degrees of freedom and we show that the translational Doppler effect has its rotational counterpart. This rotational Doppler effect leads to an additional broadening of the spectral line of the same magnitude as the Doppler broadening caused by translational thermal motion. The rotational Doppler broadening as well as the rotational recoil broadening is sensitive to the molecular orbital from which the photoelectron is ejected. This broadening should be taken into account in analysis of x-ray photoemission spectra of super-high resolution and it can be directly observed using x-ray pump-probe spectroscopy.

  8. ZAKKAROFF et al.: RECOVERY OF SLICE ROTATIONS IN CARDIAC MR SERIES 1 Recovery of Slice Rotations with the Stack

    E-Print Network [OSTI]

    Magee, Derek

    ZAKKAROFF et al.: RECOVERY OF SLICE ROTATIONS IN CARDIAC MR SERIES 1 Recovery of Slice Rotations with the Stack Alignment Transform in Cardiac MR Series Constantine Zakkaroff1 mnkz@leeds.ac.uk Aleksandra Radjenovic2 a.radjenovic@leeds.ac.uk John Greenwood3 j.greenwood@leeds.ac.uk Derek Magee1 d

  9. Molecular heat pump for rotational states

    E-Print Network [OSTI]

    C. Lazarou; M. Keller; B. M. Garraway

    2010-01-25T23:59:59.000Z

    In this work we investigate the theory for three different uni-directional population transfer schemes in trapped multilevel systems which can be utilized to cool molecular ions. The approach we use exploits the laser-induced coupling between the internal and motional degrees of freedom so that the internal state of a molecule can be mapped onto the motion of that molecule in an external trapping potential. By sympathetically cooling the translational motion back into its ground state the mapping process can be employed as part of a cooling scheme for molecular rotational levels. This step is achieved through a common mode involving a laser-cooled atom trapped alongside the molecule. For the coherent mapping we will focus on adiabatic passage techniques which may be expected to provide robust and efficient population transfers. By applying far-detuned chirped adiabatic rapid passage pulses we are able to achieve an efficiency of better than 98% for realistic parameters and including spontaneous emission. Even though our main focus is on cooling molecular states, the analysis of the different adiabatic methods has general features which can be applied to atomic systems.

  10. Solid State Replacement of Rotating Mirror Cameras

    SciTech Connect (OSTI)

    Frank, A M; Bartolick, J M

    2006-08-25T23:59:59.000Z

    Rotating mirror cameras have been the mainstay of mega-frame per second imaging for decades. There is still no electronic camera that can match a film based rotary mirror camera for the combination of frame count, speed, resolution and dynamic range. The rotary mirror cameras are predominantly used in the range of 0.1 to 100 micro-seconds per frame, for 25 to more than a hundred frames. Electron tube gated cameras dominate the sub microsecond regime but are frame count limited. Video cameras are pushing into the microsecond regime but are resolution limited by the high data rates. An all solid state architecture, dubbed ''In-situ Storage Image Sensor'' or ''ISIS'', by Prof. Goji Etoh, has made its first appearance into the market and its evaluation is discussed. Recent work at Lawrence Livermore National Laboratory has concentrated both on evaluation of the presently available technologies and exploring the capabilities of the ISIS architecture. It is clear though there is presently no single chip camera that can simultaneously match the rotary mirror cameras, the ISIS architecture has the potential to approach their performance.

  11. Round Robin Study of Rotational Strain Rheometers

    SciTech Connect (OSTI)

    Clifford, M.J.

    2000-02-16T23:59:59.000Z

    A round robin of testing was performed to compare the performance of rotational dynamic mechanical spectrometers being used within the nuclear weapons complex. Principals from Sandia National Laboratories/New Mexico; Lockheed Martin Y12 Plant at Oak Ridge, Tennessee; Los Alamos National Laboratory, New Mexico (polycarbonate only); and Honeywell Federal Manufacturing and Technologies (FM and T), Kansas City, MO, performed identical testing of hydrogen blown polysiloxane S5370 and bisphenol-A polycarbonate. Over an oscillation frequency sweep from 0.01 Hz to 15.9 Hz at 135 C, each site produced shear storage modulus values with standard deviations of less than 5%. The data from Sandia, Y12, and Kansas City agreed to within 4%, while the Los Alamos data differed by as much as 13%. Storage modulus values for a frequency sweep of the S5370 at 35 C had standard deviations between 6% and 8%, and site-to-site agreement averaged 3%. The shear loss modulus values had standard deviations of 5%, 7%, and 52% for the sites participating, while the results differed by 12% on average.

  12. Molecular heat pump for rotational states

    E-Print Network [OSTI]

    Lazarou, C; Garraway, B M

    2010-01-01T23:59:59.000Z

    In this work we investigate the theory for three different uni-directional population transfer schemes in trapped multilevel systems which can be utilized to cool molecular ions. The approach we use exploits the laser-induced coupling between the internal and motional degrees of freedom so that the internal state of a molecule can be mapped onto the motion of that molecule in an external trapping potential. By sympathetically cooling the translational motion back into its ground state the mapping process can be employed as part of a cooling scheme for molecular rotational levels. This step is achieved through a common mode involving a laser-cooled atom trapped alongside the molecule. For the coherent mapping we will focus on adiabatic passage techniques which may be expected to provide robust and efficient population transfers. By applying far-detuned chirped adiabatic rapid passage pulses we are able to achieve an efficiency of better than 98% for realistic parameters and including spontaneous emission. Even...

  13. Solar rotation rate and its gradients during cycle 23

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu; S. M. Chitre

    2008-05-22T23:59:59.000Z

    Available helioseismic data now span almost the entire solar activity cycle 23 making it possible to study solar-cycle related changes of the solar rotation rate in detail. In this paper we study how the solar rotation rate, in particular, the zonal flows change with time. In addition to the zonal flows that show a well known pattern in the solar convection zone, we also study changes in the radial and latitudinal gradients of the rotation rate, particularly in the shear layer that is present in the immediate sub-surface layers of the Sun. In the case of the zonal-flow pattern, we find that the band indicating fast rotating region close to the equator seems to have bifurcated around 2005. Our investigation of the rotation-rate gradients show that the relative variation in the rotation-rate gradients is about 20% or more of their average values, which is much larger than the relative variation in the rotation rate itself. These results can be used to test predictions of various solar dynamo models.

  14. Novel rotating field probe for inspection of tubes

    SciTech Connect (OSTI)

    Xin, J.; Tarkleson, E.; Lei, N.; Udpa, L.; Udpa, S. S. [Nondestructive Evaluation Laboratory, Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI, 48824 (United States)

    2012-05-17T23:59:59.000Z

    Inspection of steam generator tubes in nuclear power plants is extremely critical for safe operation of the power plant. In the nuclear industry, steam generator tube inspection using eddy current techniques has evolved over the years from a single bobbin coil, to rotating probe coil (RPC) and array probe, in an attempt to improve the speed and reliability of inspection. The RPC probe offers the accurate spatial resolution but involves complex mechanical rotation. This paper presents a novel design of eddy current probes based on rotating fields produced by three identical coils excited by a balanced three-phase supply. The sensor thereby achieves rotating probe functionality by electronic means and eliminates the need for mechanical rotation. The field generated by the probe is largely radial that result in induced currents that flow circularly around the radial axis and rotating around the tube at a synchronous speed effectively producing induced eddy currents that are multidirectional. The probe will consequently be sensitive to cracks of all orientations in the tube wall. The finite element model (FEM) results of the rotating fields and induced currents are presented. A prototype probe is being built to validate simulation results.

  15. Centrifugal force induced by relativistically rotating spheroids and cylinders

    E-Print Network [OSTI]

    Joseph Katz; Donald Lynden-Bell; Jiri Bicak

    2011-02-25T23:59:59.000Z

    Starting from the gravitational potential of a Newtonian spheroidal shell we discuss electrically charged rotating prolate spheroidal shells in the Maxwell theory. In particular we consider two confocal charged shells which rotate oppositely in such a way that there is no magnetic field outside the outer shell. In the Einstein theory we solve the Ernst equations in the region where the long prolate spheroids are almost cylindrical; in equatorial regions the exact Lewis "rotating cylindrical" solution is so derived by a limiting procedure from a spatially bound system. In the second part we analyze two cylindrical shells rotating in opposite directions in such a way that the static Levi-Civita metric is produced outside and no angular momentum flux escapes to infinity. The rotation of the local inertial frames in flat space inside the inner cylinder is thus exhibited without any approximation or interpretational difficulties within this model. A test particle within the inner cylinder kept at rest with respect to axes that do not rotate as seen from infinity experiences a centrifugal force. Although the spacetime there is Minkowskian out to the inner cylinder nevertheless that space has been induced to rotate, so relative to the local inertial frame the particle is traversing a circular orbit.

  16. Centrifugal force reversal from the perspective of rigidly rotating observer

    E-Print Network [OSTI]

    Giorgi Dalakishvili

    2011-12-26T23:59:59.000Z

    In previous studies the dynamics of the relativistic particle moving along the rotating pipe was investigated. The simple gedanken experiment was considered. It was shown that at large enough velocities a centrifugal force acting on the bead changes its usual sign and attracts towards the rotation axis. The authors studied motion of the particle along the rotating straight pipe in the frame of the observer located in the center of rotation, also dynamics of centrifugally accelerated relativistic particle was studied in the laboratory frame. In the both cases it was shown that centrifugal force changes sign. Recently the problem was studied in the frame of stationary observers. It was argued that centrifugal acceleration reversal is not frame invariant effect. In the present paper we consider motion of particle along the rotating straight line in the frame of an arbitrary stationary observer located at certain distance form the center of rotation and rigidly rotating with constant angular velocity. It is shown that any stationary observer could detect reversal of centrifugal acceleration.

  17. Double-Couple Earthquake Source: Symmetry and Rotation

    E-Print Network [OSTI]

    Yan Y. Kagan

    2012-07-20T23:59:59.000Z

    We consider statistical analysis of double couple (DC) earthquake focal mechanism orientation. The symmetry of DC changes with its geometrical properties, and the number of 3-D rotations one DC source can be transformed into another depends on its symmetry. Four rotations exist in a general case of DC with the nodal-plane ambiguity, two transformations if the fault plane is known, and one rotation if the sides of the fault plane are known. The symmetry of rotated objects is extensively analyzed in statistical material texture studies, and we apply their results to analyzing DC orientation. We consider theoretical probability distributions which can be used to approximate observational patterns of focal mechanisms. Uniform random rotation distributions for various DC sources are discussed, as well as two non-uniform distributions: the rotational Cauchy and von Mises-Fisher. We discuss how parameters of these rotations can be estimated by a statistical analysis of earthquake source properties in global seismicity. We also show how earthquake focal mechanism orientations can be displayed on the Rodrigues vector space.

  18. Temporal variations of the rotation rate in the solar interior

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2000-04-25T23:59:59.000Z

    The temporal variations of the rotation rate in the solar interior are studied using frequency splittings from Global Oscillations Network Group (GONG) data obtained during the period 1995-99. We find alternating latitudinal bands of faster and slower rotation which appear to move towards the equator with time - similar to the torsional oscillations seen at the solar surface. This flow pattern appears to persist to a depth of about 0.1R_sun and in this region its magnitude is well correlated with solar activity indices. We do not find any periodic or systematic changes in the rotation rate near the base of the convection zone.

  19. Quasi-toroidal oscillations in rotating relativistic stars

    E-Print Network [OSTI]

    Yasufumi Kojima

    1997-09-02T23:59:59.000Z

    Quasi-toroidal oscillations in slowly rotating stars are examined in the framework of general relativity. The oscillation frequency to first order of the rotation rate is not a single value even for uniform rotation unlike the Newtonian case. All the oscillation frequencies of the r-modes are purely neutral and form a continuous spectrum limited to a certain range. The allowed frequencies are determined by the resonance condition between the perturbation and background mean flow. The resonant frequency varies with the radius according to general relativistic dragging effect.

  20. 3D rotational diffusion microrheology using 2D video microscopy

    E-Print Network [OSTI]

    Rémy Colin; Minhao Yan; Loudjy Chevry; Jean-François Berret; Bérengère Abou

    2012-01-05T23:59:59.000Z

    We propose a simple way to perform three-dimensional (3D) rotational microrheology using two-dimensional (2D) video microscopy. The 3D rotational brownian motion of micrometric wires in a viscous fluid is deduced from their projection on the focal plane of an optical microscope objective. The rotational diffusion coefficient of the wires of length between 1-100 \\mu m is extracted, as well as their diameter distribution in good agreement with electron microscopy measurements. This is a promising way to characterize soft visco-elastic materials, and probe the dimensions of anisotropic objects.

  1. Improvement of the edge rotation diagnostic spectrum analysis via simulation

    SciTech Connect (OSTI)

    Luo, J.; Zhuang, G., E-mail: ge-zhuang@hust.edu.cn; Cheng, Z. F.; Zhang, X. L.; Hou, S. Y.; Cheng, C. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-11-15T23:59:59.000Z

    The edge rotation diagnostic (ERD) system has been developed on the Joint Texas Experimental Tokamak to measure the edge toroidal rotation velocity by observing the shifted wavelength of carbon V (C V 227.09 nm). Since the measured spectrum is an integrated result along the viewing line from the plasma core to the edge, a method via simulation has been developed to analyze the ERD spectrum. With the necessary parameters such as C V radiation profile and the ion temperature profile, a local rotation profile at the normalized minor radius of 0.5-1 is obtained.

  2. Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics in orthorhombic ammonia borane. Quasielastic neutron scattering of -NH3 and -BH3 rotational dynamics in...

  3. Analysis and experiments for contra-rotating propeller

    E-Print Network [OSTI]

    Kravitz, Eyal

    2011-01-01T23:59:59.000Z

    Contra-rotating propellers have renewed interest from the naval architecture community, because of the recent development of electric propulsion drives and podded propulsors. Contrarotating propulsion systems have the ...

  4. Hawking Radiation as Tunneling: the D-dimensional rotating case

    E-Print Network [OSTI]

    M. Nadalini; L. Vanzo; S. Zerbini

    2005-11-24T23:59:59.000Z

    The tunneling method for the Hawking radiation is revisited and applied to the $D$ dimensional rotating case. Emphasis is given to covariance of results. Certain ambiguities afflicting the procedure are resolved.

  5. Rotating embedded black holes: Entropy and Hawking's radiation

    E-Print Network [OSTI]

    Ng Ibohal

    2004-12-27T23:59:59.000Z

    In this paper we derive a class of rotating embedded black holes. Then we study Hawking's radiation effects on these embedded black holes. The surface gravity, entropy and angular velocity are given for each of these black holes.

  6. Contrast from rotating frame relaxation by adiabatic pulses

    DOE Patents [OSTI]

    Michaeli, Shalom (St. Paul, MN); Garwood, Michael G. (Medina, MN); Ugurbil, Kamil (Minneapolis, MN); Sorce, Dennis J. (Cockeysville, MD)

    2007-10-09T23:59:59.000Z

    This document discusses, among other things, a system and method for modulating transverse and longitudinal relaxation time contrast in a rotating frame based on a train of radio frequency pulses.

  7. Title of dissertation: TURBULENT SHEAR FLOW IN A RAPIDLY ROTATING

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    ABSTRACT Title of dissertation: TURBULENT SHEAR FLOW IN A RAPIDLY ROTATING SPHERICAL ANNULUS Daniel S. Zimmerman, Doctor of Philosophy, 2010 Dissertation directed by: Professor Daniel P. Lathrop Department of Physics This dissertation presents experimental measurements of torque, wall shear stress

  8. alternately rotating walls: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chiral molecules act as propellers. When the axis is blocked at the lateral walls of the trough, the accumulated rotation inside creates huge splays and bends. We discuss the...

  9. Numerical Study of Flow and Heat Transfer in Rotating Microchannels

    E-Print Network [OSTI]

    Roy, Pratanu

    2014-10-07T23:59:59.000Z

    Investigation of fluid flow and heat transfer in rotating microchannels is important for centrifugal microfluidics, which has emerged as an advanced technique in biomedical applications and chemical separations. The centrifugal force...

  10. ROTATING LINE CAMERAS: EPIPOLAR GEOMETRY AND SPATIAL SAMPLING

    E-Print Network [OSTI]

    project 3D scenes on a cylindric sur- face, where one or multiple rotating sensor lines allow to compose for controlling this error, allowing to adjust the camera position- ing at the time of photo shooting. The report

  11. Dynamo Saturation in Rapidly Rotating Solar-Type Stars

    E-Print Network [OSTI]

    Kitchatinov, L L

    2015-01-01T23:59:59.000Z

    The magnetic activity of solar-type stars generally increases with stellar rotation rate. The increase, however, saturates for fast rotation. The Babcock-Leighton mechanism of stellar dynamos saturates as well when the mean tilt-angle of active regions approaches ninety degrees. Saturation of magnetic activity may be a consequence of this property of the Babcock-Leighton mechanism. Stellar dynamo models with a tilt-angle proportional to the rotation rate are constructed to probe this idea. Two versions of the model - treating the tilt-angles globally and using Joy's law for its latitude dependence - are considered. Both models show a saturation of dynamo-generated magnetic flux at high rotation rates. The model with latitude-dependent tilt-angles shows also a change in dynamo regime in the saturation region. The new regime combines a cyclic dynamo at low latitudes with an (almost) steady polar dynamo.

  12. axis rotating states: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    20 21 22 23 24 25 Next Page Last Page Topic Index 21 Rotation speed and stellar axis inclination from p modes: How CoRoT would see other suns Astrophysics (arXiv) Summary: In the...

  13. Aerodynamic performance measurements in a counter-rotating aspirated compressor

    E-Print Network [OSTI]

    Onnée, Jean-François

    2005-01-01T23:59:59.000Z

    This thesis is an experimental investigation of the aerodynamic performances of a counter-rotating aspirated compressor. This compressor is implemented in a blow-down facility, which gives rigorous simulation of the ...

  14. Ferrofluid surface and volume flows in uniform rotating magnetic fields

    E-Print Network [OSTI]

    Elborai, Shihab M. (Shihab Mahmoud), 1977-

    2006-01-01T23:59:59.000Z

    Ferrofluid surface and volume effects in uniform dc and rotating magnetic fields are studied. Theory and corroborating measurements are presented for meniscus shapes and resulting surface driven flows, spin-up flows, and ...

  15. Reducing Collective Quantum State Rotation Errors with Reversible Dephasing

    E-Print Network [OSTI]

    Kevin C. Cox; Matthew A. Norcia; Joshua M. Weiner; Justin G. Bohnet; James K. Thompson

    2014-07-16T23:59:59.000Z

    We demonstrate that reversible dephasing via inhomogeneous broadening can greatly reduce collective quantum state rotation errors, and observe the suppression of rotation errors by more than 21 dB in the context of collective population measurements of the spin states of an ensemble of $2.1 \\times 10^5$ laser cooled and trapped $^{87}$Rb atoms. The large reduction in rotation noise enables direct resolution of spin state populations 13(1) dB below the fundamental quantum projection noise limit. Further, the spin state measurement projects the system into an entangled state with 9.5(5) dB of directly observed spectroscopic enhancement (squeezing) relative to the standard quantum limit, whereas no enhancement would have been obtained without the suppression of rotation errors.

  16. Abstract: Development and Deployment of a Short Rotation Woody...

    Broader source: Energy.gov (indexed) [DOE]

    highlights a project that will develop a single pass cut and chip harvesting system for short rotation woody crops that will improve the harvesting and logistic costs of processing...

  17. Supernova Seismology: Gravitational Wave Signatures of Rapidly Rotating Core Collapse

    E-Print Network [OSTI]

    Fuller, Jim; Abdikamalov, Ernazar; Ott, Christian

    2015-01-01T23:59:59.000Z

    Gravitational waves (GW) generated during a core-collapse supernova open a window into the heart of the explosion. At core bounce, progenitors with rapid core rotation rates exhibit a characteristic GW signal which can be used to constrain the properties of the core of the progenitor star. We investigate the dynamics of rapidly rotating core collapse, focusing on hydrodynamic waves generated by the core bounce and the GW spectrum they produce. The centrifugal distortion of the rapidly rotating proto-neutron star (PNS) leads to the generation of axisymmetric quadrupolar oscillations within the PNS and surrounding envelope. Using linear perturbation theory, we estimate the frequencies, amplitudes, damping times, and GW spectra of the oscillations. Our analysis provides a qualitative explanation for several features of the GW spectrum and shows reasonable agreement with nonlinear hydrodynamic simulations, although a few discrepancies due to non-linear/rotational effects are evident. The dominant early postbounce...

  18. The economics of rotating savings and credit associations

    E-Print Network [OSTI]

    Besley, Timothy

    1990-01-01T23:59:59.000Z

    This paper examines the role and performance of an institution for allocating savings which is observed world wide - rotating savings and credit associations. We develop a general equilibrium model of an economy with an ...

  19. Measurement of the Integrated Faraday Rotations of BL Lac Objects

    E-Print Network [OSTI]

    A. B. Pushkarev

    2003-07-09T23:59:59.000Z

    We present the results of multi-frequency polarization VLA observations of radio sources from the complete sample of northern, radio-bright BL Lac objects compiled by H. Kuhr and G. Schmidt. These were used to determine the integrated rotation measures of 18 objects, 15 of which had never been measured previously, which hindered analysis of the intrinsic polarization properties of objects in the complete sample. These measurements make it possible to correct the observed orientations of the linear polarizations of these sources for the effect of Faraday rotation. The most probable origin for Faraday rotation in these objects is the Galactic interstellar medium. The results presented complete measurements of the integrated rotation measures for all 34 sources in the complete sample of BL Lac objects.

  20. Design and cavitation performance of contra-rotating propellers

    E-Print Network [OSTI]

    Laskos, Dimitrios

    2010-01-01T23:59:59.000Z

    Improvement of the propulsive efficiency of ships has always been one of the main objectives for naval architects and marine engineers. Contra-Rotating propellers (CRP) are propulsor configurations offering higher efficiency ...

  1. On the Planetary acceleration and the Rotation of the Earth

    E-Print Network [OSTI]

    Arbab I. Arbab

    2007-08-06T23:59:59.000Z

    We have developed a model for the Earth rotation that gives a good account (data) of the Earth astronomical parameters. These data can be compared with the ones obtained using space-base telescopes. The expansion of the universe has an impact on the rotation of planets, and in particular, the Earth. The expansion of the universe causes an acceleration that is exhibited by all planets.

  2. Manipulator for rotating and translating a sample holder

    DOE Patents [OSTI]

    van de Water, Jeroen (Breugel, NL); van den Oetelaar, Johannes (Eindhoven, NL); Wagner, Raymond (Gorinchem, NL); Slingerland, Hendrik Nicolaas (Venlo, NL); Bruggers, Jan Willem (Eindhoven, NL); Ottevanger, Adriaan Huibert Dirk (Malden, NL); Schmid, Andreas (Berkeley, CA); Olson, Eric A. (Champaign, IL); Petrov, Ivan G. (Champaign, IL); Donchev, Todor I. (Urbana, IL); Duden, Thomas (Kensington, CA)

    2011-02-08T23:59:59.000Z

    A manipulator for use in e.g. a Transmission Electron Microscope (TEM) is described, said manipulator capable of rotating and translating a sample holder (4). The manipulator clasps the round sample holder between two members (3A, 3B), said members mounted on actuators (2A, 2B). Moving the actuators in the same direction results in a translation of the sample holder, while moving the actuators in opposite directions results in a rotation of the sample holder.

  3. Balancing of high speed, flexible rotating shafts across critical speeds 

    E-Print Network [OSTI]

    White, Gary Paul

    1977-01-01T23:59:59.000Z

    BALANCING OF HIGH SPEED, FLEXIBLE ROTATING SHAFTS ACROSS CRITICAL SPEEDS A Thesis by Gary Paul White Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1977 Major Subject: Mechanical Engineering Gary Paul White 1977 BALANCING OF HIGH SPEED, FLEXIBLE ROTATING SHAFTS ACROSS CRITICAL SPEEDS A Thesis by GARY PAUL WHITE Approved as to style and content by: Head of Department Member August...

  4. Rotation-induced nonlinear wavepackets in internal waves

    SciTech Connect (OSTI)

    Whitfield, A. J., E-mail: ashley.whitfield.12@ucl.ac.uk; Johnson, E. R., E-mail: e.johnson@ucl.ac.uk [Department of Mathematics, University College London, London WC1E 6BT (United Kingdom)

    2014-05-15T23:59:59.000Z

    The long time effect of weak rotation on an internal solitary wave is the decay into inertia-gravity waves and the eventual formation of a localised wavepacket. Here this initial value problem is considered within the context of the Ostrovsky, or the rotation-modified Korteweg-de Vries (KdV), equation and a numerical method for obtaining accurate wavepacket solutions is presented. The flow evolutions are described in the regimes of relatively-strong and relatively-weak rotational effects. When rotational effects are relatively strong a second-order soliton solution of the nonlinear Schrödinger equation accurately predicts the shape, and phase and group velocities of the numerically determined wavepackets. It is suggested that these solitons may form from a local Benjamin-Feir instability in the inertia-gravity wave-train radiated when a KdV solitary wave rapidly adjusts to the presence of strong rotation. When rotational effects are relatively weak the initial KdV solitary wave remains coherent longer, decaying only slowly due to weak radiation and modulational instability is no longer relevant. Wavepacket solutions in this regime appear to consist of a modulated KdV soliton wavetrain propagating on a slowly varying background of finite extent.

  5. Magneto-Rotational Transport in the Early Sun

    E-Print Network [OSTI]

    Kristen Menou; Joel LeMer

    2006-06-14T23:59:59.000Z

    Angular momentum transport must have occurred in the Sun's radiative zone to explain its current solid body rotation. We survey the stability of the early Sun's radiative zone with respect to diffusive rotational instabilities, for a variety of plausible past configurations. We find that the (faster rotating) early Sun was prone to rotational instabilities even if only weak levels of radial differential rotation were present, while the current Sun is not. Stability domains are determined by approximate balance between dynamical and diffusive timescales, allowing generalizations to other stellar contexts. Depending on the strength and geometry of the weak magnetic field present, the fastest growing unstable mode can be hydrodynamic or magneto-hydrodynamic (MHD) in nature. Our results suggest that diffusive MHD modes may be more efficient at transporting angular momentum than their hydrodynamic (``Goldreich-Schubert-Fricke'') counterparts because the minimum spatial scale required for magnetic tension to be destabilizing limits the otherwise very small scales favored by double-diffusive instabilities. Diffusive magneto-rotational instabilities are thus attractive candidates for angular momentum transport in the early Sun's radiative zone.

  6. ROTATION AND MULTIPLE STELLAR POPULATION IN GLOBULAR CLUSTERS

    SciTech Connect (OSTI)

    Bekki, Kenji [ICRAR, M468, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009 (Australia)

    2010-11-20T23:59:59.000Z

    We investigate structure and kinematics of the second generation of stars (SG) formed from gaseous ejecta of the first generation of stars (FG) in forming globular clusters (GCs). We consider that SG can be formed from gaseous ejecta from asymptotic giant branch stars of FG with the initial total mass of 10{sup 6} M {sub sun}-10{sup 8} M {sub sun} to explain the present masses of the Galactic GCs. Our three-dimensional hydrodynamical simulations with star formation show that SG formed in the central regions of FG can have a significant amount of rotation (V/{sigma}{approx} 0.8-2.5). The rotational amplitude of SG can depend strongly on the initial kinematics of FG. We thus propose that some GCs composed of FG and SG had a significant amount of rotation when they were formed. We also suggest that although later long-term ({approx}10 Gyr) dynamical evolution of stars can smooth out the initial structural and kinematical differences between FG and SG to a large extent, initial flattened structures and rotational kinematics of SG can be imprinted on shapes and internal rotation of the present GCs. We discuss these results in terms of internal rotation observed in the Galactic GCs.

  7. Equatorial symmetry of Boussinesq convective solutions in a rotating spherical shell allowing rotation of the inner and outer spheres

    SciTech Connect (OSTI)

    Kimura, Keiji; Takehiro, Shin-ichi; Yamada, Michio [Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502 (Japan)

    2014-08-15T23:59:59.000Z

    We investigate properties of convective solutions of the Boussinesq thermal convection in a moderately rotating spherical shell allowing the respective rotation of the inner and outer spheres due to the viscous torque of the fluid. The ratio of the inner and outer radii of the spheres, the Prandtl number, and the Taylor number are fixed to 0.4, 1, and 500{sup 2}, respectively. The Rayleigh number is varied from 2.6 × 10{sup 4} to 3.4 × 10{sup 4}. In this parameter range, the behaviours of obtained asymptotic convective solutions are almost similar to those in the system whose inner and outer spheres are restricted to rotate with the same constant angular velocity, although the difference is found in the transition process to chaotic solutions. The convective solution changes from an equatorially symmetric quasi-periodic one to an equatorially symmetric chaotic one, and further to an equatorially asymmetric chaotic one, as the Rayleigh number is increased. This is in contrast to the transition in the system whose inner and outer spheres are assumed to rotate with the same constant angular velocity, where the convective solution changes from an equatorially symmetric quasi-periodic one, to an equatorially asymmetric quasi-periodic one, and to equatorially asymmetric chaotic one. The inner sphere rotates in the retrograde direction on average in the parameter range; however, it sometimes undergoes the prograde rotation when the convective solution becomes chaotic.

  8. From static to rotating to conformal static solutions: Rotating imperfect fluid wormholes with(out) electric or magnetic field

    E-Print Network [OSTI]

    Mustapha Azreg-Aïnou

    2014-04-16T23:59:59.000Z

    We derive a shortcut stationary metric formula for generating imperfect fluid rotating solutions, in Boyer-Lindquist coordinates, from spherically symmetric static ones. We explore the properties of the curvature scalar and stress-energy tensor for all types of rotating regular solutions we can generate without restricting ourselves to specific examples of regular solutions (regular black holes or wormholes). We show through examples how it is generally possible to generate an imperfect fluid regular rotating solution via radial coordinate transformations. We derive rotating wormholes that are modeled as imperfect fluids and discuss their physical properties that are independent on the way the stress-energy tensor is interpreted. A solution modeling an imperfect fluid rotating loop black hole is briefly discussed. We then specialize to the recently discussed stable exotic dust Ellis wormhole emerged in a source-free radial electric or magnetic field, generate its, conjecturally stable, rotating counterpart which turns out to be an exotic imperfect fluid wormhole and determine the stress-energy tensor of both the imperfect fluid and the electric or magnetic field.

  9. OSHA Form completed and signed by the Rotation Mentor and returned to the Graduate Office. A. I understand that I will need to submit a Rotation Evaluation Form for this student at the end of the rotation.

    E-Print Network [OSTI]

    Yates, Andrew

    Part III OSHA Form completed and signed by the Rotation Mentor and returned to the Graduate Office: MENTOR'S NAME: Student Signature Date Rotation Mentor Signature Date Rotation Department's Administrator Signature Date Thesis Mentor Signature Date Declared Department's Administrator Signature Date Assoc. Dean

  10. Division of Astronomy and Space Physics MHD Theory of Rotating Tokamak Plasmas

    E-Print Network [OSTI]

    Division of Astronomy and Space Physics MHD Theory of Rotating Tokamak Plasmas in collaboration stability theory of rotating tokamak plasmas. The research is a part of the Swedish and European research rotation and rotation shear on various MHD modes in tokamak plasmas [3, 4, 5] Fig. 3: Stabilization

  11. The rotational behavior of Kepler Stars with Planets

    E-Print Network [OSTI]

    Paz-Chinchón, F; Bravo, J P; de Freitas, D B; Lopes, C E Ferreira; Alves, S; Catelan, M; Martins, B L Canto; De Medeiros, J R

    2015-01-01T23:59:59.000Z

    We analyzed the host stars of the present sample of confirmed planets detected by Kepler and Kepler Objects of Interest (KOI) to compute new photometric rotation periods and to study the behavior of their angular momentum. Lomb-Scargle periodograms and wavelet maps were computed for 3,807 stars. For 540 of these stars, we were able to detect rotational modulation of the light curves at a significance level of greater than 99%. For 63 of these 540 stars, no rotation measurements were previously available in the literature. According to the published masses and evolutionary tracks of the stars in this sample, the sample is composed of M- to F-type stars (with masses of 0.48-1.53 M$_{\\odot}$) with rotation periods that span a range of 2 to 89 days. These periods exhibit an excellent agreement with previously reported (for the stars for which such values are available), and the observed rotational period distribution strongly agrees with theoretical predictions. Furthermore, for the 540 sources considered here, t...

  12. Rotational stability of a long field-reversed configuration

    SciTech Connect (OSTI)

    Barnes, D. C., E-mail: coronadocon@msn.com; Steinhauer, L. C. [Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy, Rancho Santa Margarita, California 92688 (United States)

    2014-02-15T23:59:59.000Z

    Rotationally driven modes of long systems with dominantly axial magnetic field are considered. We apply the incompressible model and order axial wavenumber small. A recently developed gyro-viscous model is incorporated. A one-dimensional equilibrium is assumed, but radial profiles are arbitrary. The dominant toroidal (azimuthal) mode numbers ?=1 and ?=2 modes are examined for a variety of non-reversed (B) and reversed profiles. Previous results for both systems with rigid rotor equilibria are reproduced. New results are obtained by incorporation of finite axial wavenumber and by relaxing the assumption of rigid electron and ion rotation. It is shown that the frequently troublesome ?=2 field reversed configuration (FRC) mode is not strongly affected by ion kinetic effects (in contrast to non-reversed cases) and is likely stabilized experimentally only by finite length effects. It is also shown that the ?=1 wobble mode has a complicated behavior and is affected by a variety of configuration and profile effects. The rotationally driven ?=1 wobble is completely stabilized by strong rotational shear, which is anticipated to be active in high performance FRC experiments. Thus, observed wobble modes in these systems are likely not driven by rotation alone.

  13. Light defection due to a charged, rotating body

    E-Print Network [OSTI]

    Sarani Chakraborty; A. K. Sen

    2014-06-05T23:59:59.000Z

    According to GTR and subsequent developments in the field, it is known that there are three factors namely mass, rotation and charge that can influence the space-time geometry. Accordingly, we discuss the effect of space-time geometry of a charged, rotating body on the motion of the light ray. We obtained the expression for equatorial defection of light due to such a body up to fourth order term. In our expression for defection angle it is clear that charge can influence the path of light ray. We used the null geodesic approach of light ray for our calculation. If we set the charge to zero our expression of bending angle gets reduced to the Kerr equatorial bending angle.If we set rotation to zero our expression reduces to Resinner-Nordstr$\\ddot{o}$m defection angle and if we set both charge and rotation to zero our expression reduces to Schwarzschild bending angle. However, we get non-zero bending angle for a hypothetical massless, rotating, charged body.

  14. Rotational viscometer for high-pressure high-temperature fluids

    DOE Patents [OSTI]

    Carr, Kenneth R. (Knoxville, TN)

    1985-01-01T23:59:59.000Z

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer includes a substantially non-magnetic tube having a closed end and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are (a) a second magnet which is magnetically coupled to the drive magnet and (b) a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag on the rotor causes the shaft assembly to lag the rotation of the drive magnet by an amount which is a function of the amount of viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. An output is generated indicative of the phase difference between the two waveforms.

  15. ANALYTICAL CALCULATION OF STOKES PROFILES OF ROTATING STELLAR MAGNETIC DIPOLE

    SciTech Connect (OSTI)

    Martinez Gonzalez, M. J. [Instituto de Astrofisica de Canarias, Via Lactea s/n, 38200 La Laguna, Tenerife (Spain); Asensio Ramos, A. [Departamento de Astrofisica, Universidad de La Laguna, E-38205 La Laguna, Tenerife (Spain)

    2012-08-20T23:59:59.000Z

    The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman-Doppler imaging. When the magnetic field is sufficiently weak, the circular and linear polarization profiles locally in each point of the star are proportional to the first and second derivatives of the unperturbed intensity profile, respectively. We show that the weak-field approximation (for weak lines in the case of linear polarization) can be generalized to the case of a rotating star including the Doppler effect and taking into account the integration on the stellar surface. The Stokes profiles are written as a linear combination of wavelength-dependent terms expressed as series expansions in terms of Hermite polynomials. These terms contain the surface-integrated magnetic field and velocity components. The direct numerical evaluation of these quantities is limited to rotation velocities not larger than eight times the Doppler width of the local absorption profiles. Additionally, we demonstrate that in a rotating star, the circular polarization flux depends on the derivative of the intensity flux with respect to the wavelength and also on the profile itself. Likewise, the linear polarization depends on the profile and on its first and second derivatives with respect to the wavelength. We particularize the general expressions to a rotating dipole.

  16. Steady states of the parametric rotator and pendulum

    E-Print Network [OSTI]

    Antonio O. Bouzas

    2011-03-08T23:59:59.000Z

    We discuss several steady-state rotation and oscillation modes of the planar parametric rotator and pendulum with damping. We consider a general elliptic trajectory of the suspension point for both rotator and pendulum, for the latter at an arbitrary angle with gravity, with linear and circular trajectories as particular cases. We treat the damped, non-linear equation of motion of the parametric rotator and pendulum perturbatively for small parametric excitation and damping, although our perturbative approach can be extended to other regimes as well. Our treatment involves only ordinary second-order differential equations with constant coefficients, and provides numerically accurate perturbative solutions in terms of elementary functions. Some of the steady-state rotation and oscillation modes studied here have not been discussed in the previous literature. Other well-known ones, such as parametric resonance and the inverted pendulum, are extended to elliptic parametric excitation tilted with respect to gravity. The results presented here should be accessible to advanced undergraduates, and of interest to graduate students and specialists in the field of non-linear mechanics.

  17. Temporal variations of solar rotation rate at high latitudes

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2001-08-14T23:59:59.000Z

    Frequency splitting coefficients from Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI) observations covering the period 1995--2001 are used to study temporal variations in the solar rotation rate at high latitudes. The torsional oscillation pattern in the Sun is known to penetrate to a depth of about $0.1R_\\odot$ with alternate bands of faster and slower rotating plasma. At lower latitudes the bands move towards equator with time. At higher latitudes, however, the bands appear to move towards the poles. This is similar to the observed pole-ward movement of large scale magnetic fields at high latitudes. This also supports theoretical results of pole-ward moving bands at high latitudes in some mean field dynamo models. The polar rotation rate is found to decrease between 1995 and 1999 after which it has started increasing.

  18. A nonlinear calculation of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y. [Osaka Univ., Toyonaka, Osaka (Japan). Dept. of Mechanical Engineering]|[National Aerospace Lab., Kakuda, Miyagi (Japan); Watanabe, S.; Yoshida, Y. [Osaka Univ., Toyonaka, Osaka (Japan); Kamijo, K. [National Aerospace Lab., Kakuda, Miyagi (Japan)

    1996-09-01T23:59:59.000Z

    In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed, which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The purpose of the present study is to find out the factors which determine the amplitude of each mode of rotating cavitation by taking into account several nonlinearities. A time marching nonlinear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

  19. Temporal Variations in the Sun's Rotational Kinetic Energy

    E-Print Network [OSTI]

    H. M. Antia; S. M. Chitre; D. O. Gough

    2007-11-06T23:59:59.000Z

    AIM: To study the variation of the angular momentum and the rotational kinetic energy of the Sun, and associated variations in the gravitational multipole moments, on a timescale of the solar cycle. METHOD: Inverting helioseismic rotational splitting data obtained by the Global Oscillation Network Group and by the Michelson Doppler Imager on the Solar and Heliospheric Observatory. RESULTS: The temporal variation in angular momentum and kinetic energy at high latitudes (>\\pi/4) through the convection zone is positively correlated with solar activity, whereas at low latitudes it is anticorrelated, except for the top 10% by radius where both are correlated positively. CONCLUSION: The helioseismic data imply significant temporal variation in the angular momentum and the rotational kinetic energy, and in the gravitational multipole moments. The properties of that variation will help constrain dynamical theories of the solar cycle.

  20. General Relativistic Rotation Curves in a Post-Newtonian Light

    E-Print Network [OSTI]

    Aleksandar Rakic; Dominik J. Schwarz

    2008-11-10T23:59:59.000Z

    The missing of a Keplerian fall-off in the observed galaxy rotation curves represents classical evidence for the existence of dark matter on galactic scales. There has been some recent activity concerning the potential of modelling galactic systems with the help of general relativity. This was motivated by claims that by the use of full general relativity dark matter could be made superfluous. Here we focus on possible axisymmetric and stationary solutions of Einstein's equations with rotating dust. After a short review of the current debate we pursue the idea of approaching such relativistic models in a Newtonian language. We analyse rigidly as well as differentially rotating Newtonian and Post-Newtonian spacetimes and find that it is necessary to incorporate a Post-Newtonian term in order to make physical sense.

  1. New limits on extragalactic magnetic fields from rotation measures

    E-Print Network [OSTI]

    Pshirkov, Maxim S; Urban, Federico R

    2015-01-01T23:59:59.000Z

    We take advantage of the wealth of rotation measures data contained in the NVSS catalogue to derive new, statistically robust, upper limits on the strength of extragalactic magnetic fields. We simulate the extragalactic contribution to the rotation measures for a given field strength and correlation length, by assuming that the electron density follows the distribution of Lyman-$\\alpha$ clouds. Based on the observation that rotation measures from low-luminosity distant radio sources do not exhibit any trend with redshift, while the extragalactic contribution instead grows with distance, we constrain fields with Mpc coherence length to be below 1.2 nG at the $2\\sigma$ level, and fields coherent across the entire observable Universe below 0.5 nG. These limits do not depend on the particular origin of these cosmological fields.

  2. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, A.W. III

    1995-05-02T23:59:59.000Z

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

  3. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, III, Arthur W. (Patterson, CA)

    1995-01-01T23:59:59.000Z

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1.times.10.sup.-9 torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating.

  4. Rapidly rotating neutron stars in $R$-squared gravity

    E-Print Network [OSTI]

    Yazadjiev, Stoytcho S; Kokkotas, Kostas D

    2015-01-01T23:59:59.000Z

    $f(R)$ theories of gravity are one of the most popular alternative explanations for dark energy and therefore studying the possible astrophysical implications of these theories is an important task. In the present paper we make a substantial advance in this direction by considering rapidly rotating neutron stars in $R^2$ gravity. The results are obtained numerically and the method we use is non-perturbative and self-consistent. The neutron star properties, such as mass, radius and moment of inertia, are studied in detail and the results show that rotation magnifies the deviations from general relativity and the maximum mass and moment of inertia can reach very high values. This observation is similar to previous studies of rapidly rotating neutron stars in other alternative theories of gravity, such as the scalar-tensor theories, and it can potentially lead to strong astrophysical manifestations.

  5. Regenerative braking device with rotationally mounted energy storage means

    DOE Patents [OSTI]

    Hoppie, Lyle O. (Birmingham, MI)

    1982-03-16T23:59:59.000Z

    A regenerative braking device for an automotive vehicle includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (30) and an output shaft (32), clutches (50, 56) and brakes (52, 58) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. In a second embodiment the clutches and brakes are dispensed with and the variable ratio transmission is connected directly across the input and output shafts. In both embodiments the rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft rotates faster or relative to the output shaft and are torsionally relaxed to deliver energy to the vehicle when the output shaft rotates faster or relative to the input shaft.

  6. Effects of Rotational Symmetry Breaking in Polymer-coated Nanopores

    E-Print Network [OSTI]

    Osmanovic, D; Eccleston, R C; Hoogenboom, B W; Ford, I J

    2015-01-01T23:59:59.000Z

    The statistical theory of polymers tethered around the inner surface of a cylindrical channel has traditionally employed the assumption that the equilibrium density of the polymers is independent of the azimuthal coordinate. However, simulations have shown that this rotational symmetry can be broken when there are attractive interactions between the polymers. We investigate the phases that emerge in these circumstances, and we quantify the effect of the symmetry assumption on the phase behavior of the system. In the absence of this assumption, one can observe large differences in the equilibrium densities between the rotationally symmetric case and the non-rotationally symmetric case. A simple analytical model is developed that illustrates the driving thermodynamic forces responsible for this symmetry breaking. Our results have implications for the current understanding of the polymer behavior in cylindrical nanopores.

  7. High-spin rotational structures in {sup 76}Kr

    SciTech Connect (OSTI)

    Valiente-Dobon, J.J.; Svensson, C.E.; Finlay, P.; Grinyer, G.F.; Hyland, B.; Phillips, A.A.; Schumaker, M.A. [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); O'Leary, C.D.; Jenkins, D.; Johnston-Theasby, F.; Joshi, P.; Kelsall, N.S.; Wadsworth, R. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Ragnarsson, I. [Department of Physics, Lund Institute of Technology, P.O. Box 118, S-221 00 Lund (Sweden); Andreoiu, C. [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 3BX (United Kingdom); Appelbe, D.E. [CLRC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom); Austin, R.A.E.; Cameron, J.A.; Waddington, J.C. [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4K1 (Canada); Ball, G.C. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3 (Canada)] [and others

    2005-03-01T23:59:59.000Z

    High-spin states in {sup 36}{sub 76}Kr{sub 40} have been populated in the {sup 40}Ca({sup 40}Ca,4p){sup 76}Kr fusion-evaporation reaction at a beam energy of 165 MeV and studied using the Gammasphere and Microball multidetector arrays. The ground-state band and two signature-split negative parity bands of {sup 76}Kr have been extended to {approx}30({Dirac_h}/2{pi}). Lifetime measurements using the Doppler-shift attenuation method show that the transition quadrupole moment of these three bands decrease as they approach their maximum-spin states. Two signatures of a new rotational structure with remarkably rigid rotational behavior have been identified. The high-spin properties of these rotational bands are analyzed within the framework of configuration-dependent cranked Nilsson-Strutinsky calculations.

  8. Rigidly rotating ZAMO surfaces in the Kerr spacetime

    E-Print Network [OSTI]

    Andrei V. Frolov; Valeri P. Frolov

    2014-08-27T23:59:59.000Z

    A stationary observer in the Kerr spacetime has zero angular momentum if his/her angular velocity $\\omega$ has a particular value, which depends on the position of the observer. Worldlines of such zero angular momentum observers (ZAMOs) with the same value of the angular velocity $\\omega$ form a three dimensional surface, which has the property that the Killing vectors generating time translation and rotation are tangent to it. We call such a surface a rigidly rotating ZAMO surface. This definition allows a natural generalization to the surfaces inside the black hole, where ZAMO's trajectories formally become spacelike. A general property of such a surface is that there exist linear combinations of the Killing vectors with constant coefficients which make them orthogonal on it. In this paper we discuss properties of the rigidly rotating ZAMO surfaces both outside and inside the black hole and relevance of these objects to a couple of interesting physical problems.

  9. Rotational order–disorder structure of fluorescent protein FP480

    SciTech Connect (OSTI)

    Pletnev, Sergei, E-mail: svp@ncifcrf.gov [SAIC-Frederick Inc., Basic Research Program, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Morozova, Kateryna S.; Verkhusha, Vladislav V. [Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461 (United States); Dauter, Zbigniew, E-mail: svp@ncifcrf.gov [Synchrotron Radiation Research Section, MCL, National Cancer Institute, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); SAIC-Frederick Inc., Basic Research Program, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2009-09-01T23:59:59.000Z

    An analysis of the rotational order–disorder structure of fluorescent protein FP480 is presented. In the last decade, advances in instrumentation and software development have made crystallography a powerful tool in structural biology. Using this method, structural information can now be acquired from pathological crystals that would have been abandoned in earlier times. In this paper, the order–disorder (OD) structure of fluorescent protein FP480 is discussed. The structure is composed of tetramers with 222 symmetry incorporated into the lattice in two different ways, namely rotated 90° with respect to each other around the crystal c axis, with tetramer axes coincident with crystallographic twofold axes. The random distribution of alternatively oriented tetramers in the crystal creates a rotational OD structure with statistically averaged I422 symmetry, although the presence of very weak and diffuse additional reflections suggests that the randomness is only approximate.

  10. Spin rotation of polarized beams in high energy storage ring

    E-Print Network [OSTI]

    V. G. Baryshevsky

    2006-03-23T23:59:59.000Z

    The equations for spin evolution of a particle in a storage ring are obtained considering contributions from the tensor electric and magnetic polarizabilities of the particle along with the contributions from spin rotation and birefringence effect in polarized matter of an internal target. % Study of the spin rotation and birefringence effects for a particle in a high energy storage ring provides for measurement both the spin-dependent real part of the coherent elastic zero-angle scattering amplitude and tensor electric (magnetic) polarizabilities.

  11. Scalar emission in a rotating Gödel black hole

    E-Print Network [OSTI]

    Songbai Chen; Bin Wang; Jiliang Jing

    2008-08-23T23:59:59.000Z

    We study the absorption probability and Hawking radiation of the scalar field in the rotating G\\"{o}del black hole in minimal five-dimensional gauged supergravity. We find that G\\"{o}del parameter $j$ imprints in the greybody factor and Hawking radiation. It plays a different role from the angular momentum of the black hole in the Hawking radiation and super-radiance. These information can help us know more about rotating G\\"{o}del black holes in minimal five-dimensional gauged supergravity.

  12. Graphene Monolayer Rotation on Ni(111) Facilities Bilayer Graphene Growth

    SciTech Connect (OSTI)

    Batzill M.; Sutter P.; Dahal, A.; Addou, R.

    2012-06-11T23:59:59.000Z

    Synthesis of bilayer graphene by chemical vapor deposition is of importance for graphene-based field effect devices. Here, we demonstrate that bilayer graphene preferentially grows by carbon-segregation under graphene sheets that are rotated relative to a Ni(111) substrate. Rotated graphene monolayer films can be synthesized at growth temperatures above 650 C on a Ni(111) thin-film. The segregated second graphene layer is in registry with the Ni(111) substrate and this suppresses further C-segregation, effectively self-limiting graphene formation to two layers.

  13. Fitting the Galaxy Rotation Curves: Strings versus NFW profile

    E-Print Network [OSTI]

    Yeuk-Kwan E. Cheung; Feng Xu

    2008-10-14T23:59:59.000Z

    Remarkable fit of galaxy rotation curves is achieved using a simple model from string theory. The rotation curves of the same group of galaxies are also fit using dark matter model with the generalized Navarro-Frenk-White profile for comparison. String model utilizes three free parameters vs five in the dark matter model. The average chi-squared of the string model fit is 1.649 while that of the dark matter model is 1.513. The generalized NFW profile fits marginally better at a price of two more free parameters.

  14. Rotating charged cylindrical black holes as particle accelerators

    SciTech Connect (OSTI)

    Said, Jackson Levi [Physics Department, University of Malta, Msida MSD 2080 (Malta); Adami, Kristian Zarb [Physics Department, University of Malta, Msida MSD 2080 (Malta); Physics Department, University of Oxford, Oxford, OX1 3RH (United Kingdom)

    2011-05-15T23:59:59.000Z

    It has recently been pointed out that arbitrary center-of-mass energies may be obtained for particle collisions near the horizon of an extremal Kerr black hole. We investigate this mechanism in cylindrical topology. In particular we consider the center-of-mass energies of a cylindrical black hole with an extremal rotation and charge parameter. The geodesics are first derived with a rotating charged cylindrical black hole producing the background gravitational field. Finally the center-of-mass is determined for this background and its extremal limit is taken.

  15. Study of the subpicosecond rotational molecular dynamics in liquids

    SciTech Connect (OSTI)

    Nikiforov, V G; Lobkov, Vladimir S [E.K.Zavoisky Physical-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, Kazan (Russian Federation)

    2006-10-31T23:59:59.000Z

    The parameters of the femtosecond vibration-rotation molecular dynamics of liquid acetonitrile CH{sub 3}CN, trimethylacetonitrile (CH{sub 3}){sub 3}CCN, propionitrile CH{sub 3}CH{sub 2}CN, fluoroform CHF{sub 3}, and chloroform CHCl{sub 3} are found by analysing the ultrafast optical Kerr effect. The influence of the molecular structure on the features of rotational (diffusion and libration) motions is studied. It is shown that the distribution of libration frequencies is described by the Maxwell distribution. (laser applications and other topics in quantum electronics)

  16. Effect of rotating electric field on 3D complex (dusty) plasma

    SciTech Connect (OSTI)

    Woerner, L.; Nosenko, V.; Ivlev, A. V.; Zhdanov, S. K.; Thomas, H. M.; Morfill, G. E. [Max-Planck-Institut fuer extraterrestrische Physik, D-85741 Garching (Germany); Kroll, M.; Schablinski, J.; Block, D. [Christian-Albrechts Universitaet zu Kiel, D-24118 Kiel (Germany)

    2011-06-15T23:59:59.000Z

    The effect of rotating electric field on 3D particle clusters suspended in rf plasma was studied experimentally. Spheroidal clusters were suspended inside a glass box mounted on the lower horizontal rf electrode, with gravity partially balanced by thermophoretic force. Clusters rotated in the horizontal plane, in response to rotating electric field that was created inside the box using conducting coating on its inner surfaces (''rotating wall'' technique). Cluster rotation was always in the direction of applied field and had a shear in the vertical direction. The angular speed of rotation was 10{sup 4}-10{sup 7} times lower than applied frequency. The experiment is compared to a recent theory.

  17. The Stability of Magnetized Rotating Plasmas with Superthermal Fields

    E-Print Network [OSTI]

    Martin E. Pessah; Dimitrios Psaltis

    2005-04-13T23:59:59.000Z

    During the last decade it has become evident that the magnetorotational instability is at the heart of the enhanced angular momentum transport in weakly magnetized accretion disks around neutron stars and black holes. In this paper, we investigate the local linear stability of differentially rotating, magnetized flows and the evolution of the magnetorotational instability beyond the weak-field limit. We show that, when superthermal toroidal fields are considered, the effects of both compressibility and magnetic tension forces, which are related to the curvature of toroidal field lines, should be taken fully into account. We demonstrate that the presence of a strong toroidal component in the magnetic field plays a non-trivial role. When strong fields are considered, the strength of the toroidal magnetic field not only modifies the growth rates of the unstable modes but also determines which modes are subject to instabilities. We find that, for rotating configurations with Keplerian laws, the magnetorotational instability is stabilized at low wavenumbers for toroidal Alfven speeds exceeding the geometric mean of the sound speed and the rotational speed. We discuss the significance of our findings for the stability of cold, magnetically dominated, rotating fluids and argue that, for these systems, the curvature of toroidal field lines cannot be neglected even when short wavelength perturbations are considered. We also comment on the implications of our results for the validity of shearing box simulations in which superthermal toroidal fields are generated.

  18. BLACK HOLE AURORA POWERED BY A ROTATING BLACK HOLE

    SciTech Connect (OSTI)

    Takahashi, Masaaki [Department of Physics and Astronomy, Aichi University of Education, Kariya, Aichi 448-8542 (Japan); Takahashi, Rohta, E-mail: takahasi@phyas.aichi-edu.ac.j [Cosmic Radiation Laboratory, Institute of Physical and Chemical Research, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2010-05-15T23:59:59.000Z

    We present a model for high-energy emission sources generated by a standing magnetohydrodynamical (MHD) shock in a black hole magnetosphere. The black hole magnetosphere would be constructed around a black hole with an accretion disk, where a global magnetic field could be originated by currents in the accretion disk and its corona. Such a black hole magnetosphere may be considered as a model for the central engine of active galactic nuclei, some compact X-ray sources, and gamma-ray bursts. The energy sources of the emission from the magnetosphere are the gravitational and electromagnetic energies of magnetized accreting matters and the rotational energy of a rotating black hole. When the MHD shock generates in MHD accretion flows onto the black hole, the plasma's kinetic energy and the black hole's rotational energy can convert to radiative energy. In this Letter, we demonstrate the huge energy output at the shock front by showing negative energy postshock accreting MHD flows for a rapidly rotating black hole. This means that the extracted energy from the black hole can convert to the radiative energy at the MHD shock front. When an axisymmetric shock front is formed, we expect a ring-shaped region with very hot plasma near the black hole; this would look like an 'aurora'. The high-energy radiation generated from there would carry to us the information for the curved spacetime due to the strong gravity.

  19. Rotation of the Sacrum During Bellyboard Pelvic Radiotherapy

    SciTech Connect (OSTI)

    Kasabasic, Mladen [Radiotherapy and Oncology Department, University Hospital of Osijek, Osijek (Croatia)], E-mail: mkasabasic@mefos.hr; Faj, Dario; Ivkovic, Ana; Jurkovic, Slaven; Belaj, Nenad [Radiotherapy and Oncology Department, University Hospital of Osijek, Osijek (Croatia)

    2010-04-01T23:59:59.000Z

    Patients with cervical, uterine, and rectal carcinomas are usually treated in the prone position using the bellyboard positioning device. Specific and uncomfortable prone position gives rise to uncertainties in the daily set-up of patients during the treatment. During investigation of translational movements, rotational movements of the pelvis are observed and investigated. The film portal imaging is used to discover patient positioning errors during treatment. We defined the rotational set-up errors by angle deviations of the sacrum. Thirty-six patients were included in the study; 15 patients were followed during the whole treatment and 21 during the first 5 consecutive treatment days. The image acquisitions were completed in 84%. Systematic and random positioning errors were analyzed in 725 images. Approximately half of the patients had adjusted to the bellyboard in the first few fractions, with sacrum angles remaining the same for the rest of the treatment. The other half had drifts of the sacrum angle during the whole treatment. The rotation of the sacrum during treatment ranged up to 14 deg., causing the usual set-up verification and correction procedure to result in errors up to 15 mm. Rotational movements of the patient pelvis during bellyboard pelvis radiotherapy can introduce considerable patient position error.

  20. Flow Separation Control with Rotating Cylinders James Schulmeister

    E-Print Network [OSTI]

    (February 2001): 291-326. Goal: Control flow separation to reduce hydrodynamic drag and oscillating lift layer flow of the main cylinder. This delays flow separation and reduces drag. The control effortFlow Separation Control with Rotating Cylinders James Schulmeister Dr. Jason Dahl Prof. Michael

  1. Effect of spin rotation coupling on spin transport

    SciTech Connect (OSTI)

    Chowdhury, Debashree, E-mail: debashreephys@gmail.com; Basu, B., E-mail: sribbasu@gmail.com

    2013-12-15T23:59:59.000Z

    We have studied the spin rotation coupling (SRC) as an ingredient to explain different spin-related issues. This special kind of coupling can play the role of a Dresselhaus like coupling in certain conditions. Consequently, one can control the spin splitting, induced by the Dresselhaus like term, which is unusual in a semiconductor heterostructure. Within this framework, we also study the renormalization of the spin-dependent electric field and spin current due to the k{sup ?}?p{sup ?} perturbation, by taking into account the interband mixing in the rotating system. In this paper we predict the enhancement of the spin-dependent electric field resulting from the renormalized spin rotation coupling. The renormalization factor of the spin electric field is different from that of the SRC or Zeeman coupling. The effect of renormalized SRC on spin current and Berry curvature is also studied. Interestingly, in the presence of this SRC-induced SOC it is possible to describe spin splitting as well as spin galvanic effect in semiconductors. -- Highlights: •Studied effect of spin rotation coupling on the spin electric field, spin current and Berry curvature. •In the k{sup ?}?p{sup ?} framework we study the renormalization of spin electric field and spin current. •For an inertial system we have discussed the spin splitting. •Expression for the Berry phase in the inertial system is discussed. •The inertial spin galvanic effect is studied.

  2. Rotation-reversal symmetries in crystals and handed structures

    E-Print Network [OSTI]

    Gopalan, Venkatraman

    : List of roto point groups indicated in Figure 2b that are invariance groups of a net (non-zero) spin (S of roto point groups indicated in Figure 2b that are invariance groups of non-zero (net) spin (S), non-zero (net) electric polarization (P), non-zero (net) static rotation (), and combinations thereof. Net Spin

  3. Mechanical Inhibition of Foam Formation via a Rotating Nozzle

    E-Print Network [OSTI]

    Ristenpart, William

    have been devel- oped to minimize the impact of foams [2]. Anti-foaming agents are added to prevent environmental disposal problems, and increase the overall process cost and complexity [3]. Non report a design for a rotating nozzle that prevents successive collocated impacts, thereby minimizing

  4. Rotational and divergent kinetic energy in the mesoscale model ALADIN

    E-Print Network [OSTI]

    Zagar, Nedjeljka

    energy, divergent energy, ALADIN, limited-area modelling 1. Introduction Horizontal divergenceRotational and divergent kinetic energy in the mesoscale model ALADIN By V. BLAZ ICA1 *, N. Z AGAR1 received 7 June 2012; in final form 7 March 2013) ABSTRACT Kinetic energy spectra from the mesoscale

  5. Wigner representation of the rotational dynamics of rigid tops

    E-Print Network [OSTI]

    Dmitry V. Zhdanov; Tamar Seideman

    2014-06-15T23:59:59.000Z

    We propose the general methodology to design the Wigner representations with the desired dynamical and semiclassical properties in the phase spaces with nontrivial topology. As an illustration, two representations of molecular rotations are developed to suit the computational demands of contemporary applications of laser alignment, diagnostics of reaction dynamics, studies of scattering and dissipative processes.

  6. Physica D xxx (2004) xxxxxx Nonextensive statistical mechanics for rotating

    E-Print Network [OSTI]

    Aubert, Julien

    2004-01-01T23:59:59.000Z

    Physica D xxx (2004) xxx­xxx Nonextensive statistical mechanics for rotating quasi by Elsevier B.V. doi:10.1016/j.physd.2004.01.035 #12;2 S. Jung et al. / Physica D xxx (2004) xxx­xxx been

  7. Self-Calibration from Multiple Views with a Rotating Camera

    E-Print Network [OSTI]

    Hartley, Richard

    Self-Calibration from Multiple Views with a Rotating Camera Richard I. Hartley G.E. CRD, Schenectady, NY, 12301. Email : hartley@crd.ge.com Abstract. A new practical method is given for the self-calibration orientations of the camera and calibration is computed from an analysis of point matches between the images

  8. 44-88 MHz transverse optics for the rotation section

    E-Print Network [OSTI]

    McDonald, Kirk

    44-88 MHz transverse optics for the rotation section G. Prior 02/02/2010 #12;Finding TwissBz/dz non-zero. #12;SOL model 1 (2/2) Identify the transfer map elements to the Twiss parameters

  9. INTERNAL ROTATION AND DYNAMICS OF THE SUN FROM GONG DATA

    E-Print Network [OSTI]

    Corbard, Thierry

    for the Sun's internal rotation from GONG months 4--10 averaged power spectra. 1 In keeping by the Big Bear Solar Observatory, High Altitude Obseratory, Learmonth Solor Observatory, Udaipur Solor (GONG months 4--10) power spectra. One set comprises individual m frequencies from the GONG project

  10. Multi-Touch Rotation Gestures: Performance and Ergonomics

    E-Print Network [OSTI]

    Multi-Touch Rotation Gestures: Performance and Ergonomics Eve Hoggan1 , John Williamson2 , Antti multi-touch gestures, yet little is known about the fac- tors affecting performance and ergonomics; gestures; ergonomics. ACM Classification Keywords H.5.2. User Interfaces: Evaluation/Methodology, Input De

  11. On the multipole moments of a rigidly rotating fluid body

    E-Print Network [OSTI]

    Robert Filter; Andreas Kleinwächter

    2009-02-11T23:59:59.000Z

    Based on numerical simulations and analytical calculations we formulate a new conjecture concerning the multipole moments of a rigidly rotating fluid body in equilibrium. The conjecture implies that the exterior region of such a fluid is not described by the Kerr metric.

  12. Energy and Momentum of a Class of Rotating Gravitational Waves

    E-Print Network [OSTI]

    M. Sharif

    2001-02-09T23:59:59.000Z

    We calculate energy and momentum for a class of cylindrical rotating gravitational waves using Einstein and Papapetrou's prescriptions. It is shown that the results obtained are reduced to the special case of the cylindrical gravitational waves already available in the literature.

  13. Electrostatic Interchange Instabilities of a Rotating, High-Temperature Plasma

    E-Print Network [OSTI]

    Mauel, Michael E.

    Electrostatic Interchange Instabilities of a Rotating, High-Temperature Plasma Confined by a Dipole #2 Mach Probe #1 Mach Probe #2 High-field, 0.2 MA-turn Water-cooled Magnet #12;Interchange Modes-sized/global... Fast hot electron interchange instability: drift-resonant transport; Gryokinetics; phase-space holes

  14. ROTATION NUMBERS IN THOMPSON-STEIN GROUPS AND APPLICATIONS

    E-Print Network [OSTI]

    Liousse, Isabelle

    ROTATION NUMBERS IN THOMPSON-STEIN GROUPS AND APPLICATIONS ISABELLE LIOUSSE Abstract. We study, the Thompson-Stein groups. We prove that for many Thompson-Stein groups the outer automorphism group has order 2. As another application, we construct Thompson-Stein groups which do not admit non trivial rep

  15. Solar differential rotation and properties of magnetic clouds

    E-Print Network [OSTI]

    K. Georgieva; B. Kirov; E. Gavruseva; J. Javaraiah

    2005-11-09T23:59:59.000Z

    The most geoeffective solar drivers are magnetic clouds - a subclass of coronal mass ejections (CME's) distinguished by the smooth rotation of the magnetic field inside the structure. The portion of CME's that are magnetic clouds is maximum at sunspot minimum and mimimum at sunspot maximum. This portion is determined by the amount of helicity carried away by CME's which in turn depends on the amount of helicity transferred from the solar interior to the surface, and on the surface differential rotation. The latter can increase or reduce, or even reverse the twist of emerging magnetic flux tubes, thus increasing or reducing the helicity in the corona, or leading to the violation of the hemispheric helicity rule, respectively. We investigate the CME's associated with the major geomagnetic storms in the last solar cycle whose solar sources have been identified, and find that in 10 out of 12 cases of violation of the hemispheric helicity rule or of highly geoeffective CME's with no magnetic field rotation, they originate from regions with "anti-solar" type of surface differential rotation.

  16. The solar interior - radial structure, rotation, solar activity cycle

    E-Print Network [OSTI]

    Axel Brandenburg

    2007-03-28T23:59:59.000Z

    Some basic properties of the solar convection zone are considered and the use of helioseismology as an observational tool to determine its depth and internal angular velocity is discussed. Aspects of solar magnetism are described and explained in the framework of dynamo theory. The main focus is on mean field theories for the Sun's magnetic field and its differential rotation.

  17. The Balance of Dark and Luminous Mass in Rotating Galaxies

    E-Print Network [OSTI]

    Stacy McGaugh

    2005-09-12T23:59:59.000Z

    A fine balance between dark and baryonic mass is observed in spiral galaxies. As the contribution of the baryons to the total rotation velocity increases, the contribution of the dark matter decreases by a compensating amount. This poses a fine-tuning problem for \\LCDM galaxy formation models, and may point to new physics for dark matter particles or even a modification of gravity.

  18. Faraday rotation data analysis with least-squares elliptical fitting

    SciTech Connect (OSTI)

    White, Adam D.; McHale, G. Brent; Goerz, David A.; Speer, Ron D. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2010-10-15T23:59:59.000Z

    A method of analyzing Faraday rotation data from pulsed magnetic field measurements is described. The method uses direct least-squares elliptical fitting to measured data. The least-squares fit conic parameters are used to rotate, translate, and rescale the measured data. Interpretation of the transformed data provides improved accuracy and time-resolution characteristics compared with many existing methods of analyzing Faraday rotation data. The method is especially useful when linear birefringence is present at the input or output of the sensing medium, or when the relative angle of the polarizers used in analysis is not aligned with precision; under these circumstances the method is shown to return the analytically correct input signal. The method may be pertinent to other applications where analysis of Lissajous figures is required, such as the velocity interferometer system for any reflector (VISAR) diagnostics. The entire algorithm is fully automated and requires no user interaction. An example of algorithm execution is shown, using data from a fiber-based Faraday rotation sensor on a capacitive discharge experiment.

  19. ROTATION OF WHITE LIGHT CME STRUCTURES AS INFERRED FROM

    E-Print Network [OSTI]

    Solar Observatory 40386 North Shore Lane, Big Bear City, CA 92314 Valentyna Abramenko Big Bear Solar, Wilberforce Road, Cambridge CB30WA, UK ABSTRACT Understanding the connection between the magnetic that there is a slight preference for the CMEs to rotate toward the solar equator and heliospheric current sheet (59

  20. Spin-rotation coupling in compound spin objects

    E-Print Network [OSTI]

    G. Lambiase; G. Papini

    2013-01-31T23:59:59.000Z

    We generalize spin-rotation coupling to compound spin systems. In the case of muons bound to nuclei in a storage ring the decay process acquires a modulation. Typical frequencies for $Z/A\\sim 1/2$ are $\\sim 3\\times 10^6$Hz, a factor 10 higher than the modulation observed in $g-2$ experiments.

  1. Rotational Spectroscopy of PAHs: Acenaphthene, Acenaphthylene and Fluorene

    E-Print Network [OSTI]

    Thorwirth, S; Gottlieb, C A; McCarthy, M C; Thaddeus, P

    2005-01-01T23:59:59.000Z

    Pure rotational spectra of three polycyclic aromatic hydrocarbons - acenaphthene, acenaphthylene and fluorene - have been obtained by Fourier transform microwave spectroscopy of a molecular beam and subsequently by millimeter wave absorption spectroscopy for acenaphthene and fluorene. The data presented here will be useful for deep radio astronomical searches for PAHs employing large radio telecopes.

  2. Rotational Spectroscopy of PAHs: Acenaphthene, Acenaphthylene and Fluorene

    E-Print Network [OSTI]

    S. Thorwirth; P. Theule; C. A. Gottlieb; M. C. McCarthy; P. Thaddeus

    2005-09-23T23:59:59.000Z

    Pure rotational spectra of three polycyclic aromatic hydrocarbons - acenaphthene, acenaphthylene and fluorene - have been obtained by Fourier transform microwave spectroscopy of a molecular beam and subsequently by millimeter wave absorption spectroscopy for acenaphthene and fluorene. The data presented here will be useful for deep radio astronomical searches for PAHs employing large radio telecopes.

  3. Oscillatory jets and instabilities in a rotating cylinder Yohann Dugueta

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    oscillatory jets/shear layers of fixed conical shape and can be interpreted in terms of the propagation and planetary cores, where they are spawned by boundary layer eruptions at criti- cal latitudes.16 The steady rotation of the boundaries17 and emanating from velocity discontinuities. These steady layers result from

  4. ECG Gated Tomographic reconstruction for 3-D Rotational Coronary Angiography

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    imaging techniques to improve both the safety and the efficacy of coronary angiography interventions the ground for a platform dedicated to the planning and execution of percutaneous coronary inter- ventionsECG Gated Tomographic reconstruction for 3-D Rotational Coronary Angiography Yining HU, Lizhe XIE

  5. Rotating Target Development for SNS Second Target Station

    SciTech Connect (OSTI)

    McManamy, Thomas J [ORNL; Rennich, Mark J [ORNL; Crawford, Roy K [ORNL; Geoghegan, Patrick J [ORNL; Janney, Jim G [ORNL

    2010-01-01T23:59:59.000Z

    A rotating target for the second target station (STS) at SNS has been identified as an option along with a mercury target. Evaluation of the rotating target alternative for STS has started at 1.5 MW which is considered an upper bound for the power. Previous preconceptual design work for a 3 MW rotating target is being modified for the lower power level. Transient thermal analysis for a total loss of active water cooling has been done for a simplified 2D model of the target and shielding monolith which shows that peak temperatures are well below the level at which tungsten vaporization by steam could exceed site boundary dose limits. Design analysis and integration configuration studies have been done for the target-moderator-reflector assembly which maximizes the number of neutron beam lines and provides for replacement of the target and moderators. Target building hot cell arrangement for this option will be described. An option for operation in rough vacuum without a proton beam window using Ferro fluid seals on a vertical shaft is being developed. A full scale prototypic drive module based on the 3 MW preconceptual design has been fabricated and successfully tested with a shaft and mock up target supplied by the ESS-Bilbao team. Overall planning leading to decision between mercury and the rotating target in 2011 will be discussed

  6. Cryogenic cooling with cryocooler on a rotating system

    E-Print Network [OSTI]

    Oguri, Shugo; Kawai, Masanori; Tajima, Osamu

    2013-01-01T23:59:59.000Z

    We developed a system that continuously maintains a cryocooler for long periods on a rotating table. A cryostat that holds the cryocooler is set on the table. A compressor is located on the ground and supplies high-purity (> 99.999%) and high-pressure (1.7 MPa) helium gas and electricity to the cryocooler. The operation of the cryocooler and other instruments requires the development of interface components between the ground and rotating table. A combination of access holes at the center of the table and two rotary joints allows simultaneous circulation of electricity and helium gas. The developed system provides two innovative functions under the rotating condition; cooling from room temperature and the maintenance of a cold condition for long periods. We have confirmed these abilities as well as temperature stability under a condition of continuous rotation at 20 revolutions per minute. The developed system can be applied in various fields; e.g., in tests of Lorentz invariance, searches for axion, radio as...

  7. Particle Acceleration in Rotating Modified Hayward and Bardeen Black Holes

    E-Print Network [OSTI]

    Behnam Pourhassan; Ujjal Debnath

    2015-06-10T23:59:59.000Z

    In this paper we consider rotating modified Hayward and Bardeen black holes as particle accelerators. We investigate the the center of mass energy of two colliding neutral particles with same rest masses falling from rest at infinity to near the horizons of the mentioned black holes. We also investigate the range of the particle's angular momentum and the orbit of the particle.

  8. Particle Acceleration in Rotating Modified Hayward and Bardeen Black Holes

    E-Print Network [OSTI]

    Pourhassan, Behnam

    2015-01-01T23:59:59.000Z

    In this paper we consider rotating modified Hayward and Bardeen black holes as particle accelerators. We investigate the the center of mass energy of two colliding neutral particles with same rest masses falling from rest at infinity to near the horizons of the mentioned black holes. We also investigate the range of the particle's angular momentum and the orbit of the particle.

  9. Asynchronous Control of Rotation and Translation for a Robot Vehicle

    E-Print Network [OSTI]

    Crowley, James L.

    Cartesian coordinate space. In the same sense, robot vehicles require a "vehicle controller" to commandAsynchronous Control of Rotation and Translation for a Robot Vehicle James L. Crowley Patrick Appeared in Journal of Robotics and Autonomous Systems February 1993 © 1992 James L. Crowley This work has

  10. Motor processes 1 Motor Processes in Mental Rotation1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Motor processes 1 Motor Processes in Mental Rotation1 1 M.W. wishes to thank the LPPA for its are at least in part guided by motor processes, even in the case of images of abstract objects rather than of a specific motor action. We directly test the hypothesis by means of a dual-task paradigm in which subjects

  11. Dual periodicities in the rotational modulation of Saturn narrowband emissions

    E-Print Network [OSTI]

    Gurnett, Donald A.

    Dual periodicities in the rotational modulation of Saturn narrowband emissions S.Y. Ye,1 D. A emissions is examined, restricting the spacecraft location to either the northern or the southern hemisphere of Saturn. It is found that in both hemispheres, the modulation period of 5 kHz narrowband emissions has two

  12. Quantum rotation of hydrogen in single-wall carbon nanotubes

    E-Print Network [OSTI]

    Yildirim, Taner

    be widely used as an energy carrier. Current hydrogen storage technologies, in partic- ular, are inadequate Elsevier Science B.V. All rights reserved. 1. Introduction It is desirable to develop hydrogen-based energyQuantum rotation of hydrogen in single-wall carbon nanotubes C.M. Brown a,b , T. Yildirim b , D

  13. PROOF COPY 504409PHF Standing shocks in a rotating channel

    E-Print Network [OSTI]

    Tabak, Esteban G.

    input from wind stress with energy dissipation at shocks. All the energy dissipation must be by means Street, New York, New York 10012 (Received 5 June 2003; accepted 15 June 2004) This paper discusses the stationary shallow water shocks occurring in a reentrant rotating channel with wind stress and topography

  14. Solar activity and earth rotation variability R. Abarca del Rioa,

    E-Print Network [OSTI]

    Dai, Aiguo

    to secular times scales, meteorological and climatic data are correlated with solar variability (see reviews changes in solar output could be amplified in the Earth's atmosphere. In fact, at wavelengths not visibleSolar activity and earth rotation variability R. Abarca del Rioa, *, D. Gambisb , D. Salsteinc , P

  15. Thermodynamical properties of a rotating ideal Bose gas Sebastian Kling*

    E-Print Network [OSTI]

    Pelster, Axel

    potential becomes sombrero shaped. We present an analysis for an ideal Bose gas that is confined and determine the criti- cal temperature, the condensate fraction, and the heat capac- ity of the Bose gasThermodynamical properties of a rotating ideal Bose gas Sebastian Kling* Institut für Angewandte

  16. Logarithmic Bounds for Infinite Prandtl Number Rotating Convection

    E-Print Network [OSTI]

    Constantin, Peter

    is how much of the total heat transfer is due to convec- tion. The natural measure of this quantity on the forcing parameter [1] - [6], although it has been observed that rotation plays a nontrivial role as well, Chandrasekhar [8]). This is a 1 #12; system of equations coupling

  17. Analysis of the rotational structure in the high-resolution infrared...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rotational structure in the high-resolution infrared spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-1 Analysis of the rotational structure in the high-resolution...

  18. Analysis of the Rotational Structure in the High-Resolution Infrared...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rotational Structure in the High-Resolution Infrared Spectrum of trans-Hexatriene-1-13C1; a Semiexperimental Analysis of the Rotational Structure in the High-Resolution Infrared...

  19. Jet impingement heat transfer in two-pass rotating rectangular channels

    E-Print Network [OSTI]

    Zhang, Yuming

    1996-01-01T23:59:59.000Z

    The combined effects of rotation and jet impingement on local heat transfer in a two-pass rotating rectangular channel is studied. The results of an experimental investigation on the surface heat transfer coefficients under a perforated plate...

  20. A Molecular Switch Based on Current-Driven Rotation of an Encapsulated...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Switch Based on Current-Driven Rotation of an Encapsulated Cluster within a Fullerene Cage. A Molecular Switch Based on Current-Driven Rotation of an Encapsulated Cluster within a...

  1. A Multi-State Single-Molecule Switch Actuated by Rotation of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Multi-State Single-Molecule Switch Actuated by Rotation of an Encapsulated Cluster within a Fullerene Cage. A Multi-State Single-Molecule Switch Actuated by Rotation of an...

  2. Ferrofluid spin-up flows from uniform and non-uniform rotating magnetic fields

    E-Print Network [OSTI]

    Khushrushahi, Shahriar Rohinton

    2010-01-01T23:59:59.000Z

    When ferrofluid in a cylindrical container is subjected to a rotating azimuthally directed magnetic field, the fluid "spins up" into an almost rigid-body rotation where ferrofluid nanoparticles have both a linear and an ...

  3. Nonlinear gyrokinetic simulations of intrinsic rotation in up-down asymmetric tokamaks

    E-Print Network [OSTI]

    Ball, Justin Richard

    2013-01-01T23:59:59.000Z

    Experiments and theory show that tokamak plasmas with strong toroidal rotation and rotation shear can suppress turbulent energy transport as well as allow violation of the Troyon [beta] limit. However, using external neutral ...

  4. Patterns of convection in rotating spherical R Simitev and F H Busse

    E-Print Network [OSTI]

    Simitev, Radostin D

    Patterns of convection in rotating spherical shells R Simitev and F H Busse Institute of Physics of rotating spherical shells. For recent reviews we refer to the papers by Zhang and Busse [23] and Busse [6

  5. The behavior of rotator cuff tendon cells in three-dimensional culture

    E-Print Network [OSTI]

    Gill, Harmeet (Harmeet Kaur)

    2007-01-01T23:59:59.000Z

    The rotator cuff is composed of the supraspinatus, infraspinatus, subcapularis, and teres minor tendons. Rotator cuff injuries are common athletic and occupational injuries that surgery cannot fully repair. Therefore tendon ...

  6. Eye Movements During Multi-Axis Whole-Body Rotations CHRISTOPHER J. BOCKISCH,1

    E-Print Network [OSTI]

    Haslwanter, Thomas

    Straumann, and Thomas Hasl- wanter. Eye movements during multi-axis whole-body rotations. J Neurophysiol 89

  7. System for automatically aligning a support roller system under a rotating body

    DOE Patents [OSTI]

    Singletary, B. Huston (Oak Ridge, TN)

    1983-01-01T23:59:59.000Z

    Two support rings on a rotatable drum respectively engage conically tapered nd surfaces of support rollers mounted on pivot universally relative to its axis of rotation and translate therealong. Rotation of the drum on differential conical support roller diameters causes pivotal steering and axial translation of support roller until roller is centered on support rings.

  8. System for automatically aligning a support roller system under a rotating body

    DOE Patents [OSTI]

    Singletary, B.H.

    1982-07-21T23:59:59.000Z

    Two support rings on a rotatable drum respectively engage conically tapered end surfaces of support rollers mounted on pivot universally relative to its axis of rotation and translate therealong. Rotation of the drum on differential conical support roller diameters causes pivotal steering and axial translation of support roller until roller is centered on support rings.

  9. Bifurcated states of a rotating tokamak plasma in the presence of a static error-field

    E-Print Network [OSTI]

    Fitzpatrick, Richard

    Bifurcated states of a rotating tokamak plasma in the presence of a static error-field Richard, Texas 78712 Received 20 January 1998; accepted 1 June 1998 The bifurcated states of a rotating tokamak without hindrance. The response regime of a rotating tokamak plasma in the vicinity of the rational

  10. Instability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of viscous flow inside a closed circular cylinder rotating about its axis, periodically compressed by meansInstability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a J. F. Scott are known to support inertial oscillations whose frequencies are less than twice the basic rotation rate.1

  11. Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates

    E-Print Network [OSTI]

    Wei, Jun-cheng

    Vortex-peak interaction and lattice shape in rotating two-component Bose-Einstein condensates: November 28, 2011) When a two component Bose-Einstein condensate is placed into rotation, a lattice component condensate is set into rotation, topological defects of both order parameters are created, which

  12. Hydrogen Bonds, Water Rotation and Proton Mobility Liaisons Hydrog`ene, Rotation de l'eau et Mobilit'e du

    E-Print Network [OSTI]

    Agmon, Noam

    Hydrogen Bonds, Water Rotation and Proton Mobility Liaisons Hydrog`ene, Rotation de l'eau et H 3 O + est presque immo­ bilis'e par des liaisons hydrog`ene extrâ??emement fortes. Ces derni liaisons hydrog`ene de l'eau pure. Dans l'eau en dessous de 20 0 C, la rotation des mol'ecules est plus

  13. The Stability of Magnetized Rotating Plasmas with Superthermal Fields

    E-Print Network [OSTI]

    Pessah, M E

    2004-01-01T23:59:59.000Z

    During the last decade it has become evident that the magnetorotational instability is at the heart of the enhanced angular momentum transport in weakly magnetized accretion disks around neutron stars and black holes. In this paper, we investigate the local linear stability of differentially rotating, magnetized flows and the evolution of the magnetorotational instability beyond the weak-field limit. We show that, when superthermal toroidal fields are considered, both compressibility and magnetic tension terms, related to the curvature of toroidal field lines, should be taken fully into account. We demonstrate that, contrary to the results of most previous investigations, the presence of a toroidal component in the magnetic field plays a crucial role not only in the growth rates of the unstable modes but also in determining which modes are subject to instabilities. We find that, for rotationally supported configurations, the magnetorotational instability is stabilized at low wavenumbers for toroidal Alfven sp...

  14. Thermodynamic geometry of charged rotating BTZ black holes

    SciTech Connect (OSTI)

    Akbar, M. [Center for Advanced Mathematics and Physics, National University of Sciences and Technology, H-12, Islamabad (Pakistan); Quevedo, H. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, AP 70543, Mexico, DF 04510 (Mexico); ICRANet, Dipartimento di Fisica, Universita di Roma La Sapienza, I-00185 Roma (Italy); Saifullah, K. [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan); Sanchez, A. [Departamento de Posgrado, CIIDET, AP 752, Queretaro, QRO 76000 (Mexico); Taj, S. [Center for Advanced Mathematics and Physics, National University of Sciences and Technology, H-12, Islamabad (Pakistan); ICRANet, Dipartimento di Fisica, Universita di Roma La Sapienza, I-00185 Roma (Italy)

    2011-04-15T23:59:59.000Z

    We study the thermodynamics and the thermodynamic geometries of charged rotating Banados-Teitelboim-Zanelli black holes in (2+1)-gravity. We investigate the thermodynamics of these systems within the context of the Weinhold and Ruppeiner thermodynamic geometries and the recently developed formalism of geometrothermodynamics. Considering the behavior of the heat capacity and the Hawking temperature, we show that Weinhold and Ruppeiner geometries cannot describe completely the thermodynamics of these black holes and of their limiting case of vanishing electric charge. In contrast, the Legendre invariance imposed on the metric in geometrothermodynamics allows one to describe the charged rotating Banados-Teitelboim-Zanelli black holes and their limiting cases in a consistent and invariant manner.

  15. On rotational dynamics of an NH4+ ion in water

    SciTech Connect (OSTI)

    Chang, Tsun-Mei (University of Wisconsin-Parkside); Dang, Liem X. (BATTELLE (PACIFIC NW LAB))

    2003-05-15T23:59:59.000Z

    We used molecular dynamics simulations to characterize the rotational dynamics of the NH4+ ion in liquid water. The polarizable potential models were to describe the ion-water and water-water interactions. This study complements the work of Karim and Haymet (J. Chem. Phys., 93, 5961, 1990), who employed effective pir potential models. The computed rotational diffusion coefficients of the NH4+ ion in water, which were determined from the angular momentum autocorrelation function and the angular mean-square displacement, are 0.093 x 1012 rad2/s and 0.067 x 1012 rad2/s, repectively. These results are in good agreement with the 0.075 x 1012 rad2/s value determined from the nuclear magnetic resonance (NMR) spectroscopy studies of Perrin and Gipe (J. Am. Chem. Soc., 108, 1088, 1986; Science, 238, 1393, 1987).

  16. Aerodynamic testing of a rotating wind turbine blade

    SciTech Connect (OSTI)

    Butterfield, C.P.; Nelsen, E.N.

    1990-01-01T23:59:59.000Z

    Aerodynamic, load, flow-visualization, and inflow measurements were taken on a downwind horizontal-axis wind turbine (HAWT). A video camera mounted on the rotor recorded video images of tufts attached to the low-pressure side of the blade. Strain gages, mounted every 10% of the blade's span, provided load and pressure measurements. Pressure taps at 32 chordwise positions recorded pressure distributions. Wind inflow was measured via a vertical-plane array of anemometers located 10 m upwind. The objectives of the test were to address whether airfoil pressure distributions measured on a rotating blade differed from those measured in the wind tunnel, if radial flow near or in the boundary layer of the airfoil affected pressure distributions, if dynamic stall could result in increased dynamic loads, and if the location of the separation boundary measured on the rotating blade agreed with that measured in two-dimensional flow in the wind tunnel. 6 refs., 9 figs., 1 tab.

  17. Quantum optimal control within the rotating wave approximation

    E-Print Network [OSTI]

    Maximilian Keck; Matthias M. Müller; Tommaso Calarco; Simone Montangero

    2015-03-06T23:59:59.000Z

    We study the interplay between rotating wave approximation and optimal control. In particular, we show that for a wide class of optimal control problems one can choose the control field such that the Hamiltonian becomes time-independent under the rotating wave approximation. Thus, we show how to recast the functional minimization defined by the optimal control problem into a simpler multi-variable function minimization. We provide the analytic solution to the state-to-state transfer of the paradigmatic two-level system and to the more general star configuration of an $N$-level system. We demonstrate numerically the usefulness of this approach in the more general class of connected acyclic $N$-level systems with random spectra. Finally, we use it to design a protocol to entangle Rydberg via constant laser pulses atoms in an experimentally relevant range of parameters.

  18. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, J.W.; O`Brien, D.W.

    1996-07-09T23:59:59.000Z

    An apparatus and method are disclosed for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: (1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and (2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1,000 {micro}m (1 mm or larger), compared to the 250 {micro}m diameter of laser drilling. 5 figs.

  19. Electron beam machining using rotating and shaped beam power distribution

    DOE Patents [OSTI]

    Elmer, John W. (Pleasanton, CA); O'Brien, Dennis W. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    An apparatus and method for electron beam (EB) machining (drilling, cutting and welding) that uses conventional EB guns, power supplies, and welding machine technology without the need for fast bias pulsing technology. The invention involves a magnetic lensing (EB optics) system and electronic controls to: 1) concurrently bend, focus, shape, scan, and rotate the beam to protect the EB gun and to create a desired effective power-density distribution, and 2) rotate or scan this shaped beam in a controlled way. The shaped beam power-density distribution can be measured using a tomographic imaging system. For example, the EB apparatus of this invention has the ability to drill holes in metal having a diameter up to 1000 .mu.m (1 mm or larger), compared to the 250 .mu.m diameter of laser drilling.

  20. The Age and Interior Rotation of Stars from Asteroseismology

    E-Print Network [OSTI]

    Aerts, Conny

    2015-01-01T23:59:59.000Z

    We provide a status report on the determination of stellar ages from asteroseismology for stars of various masses and evolutionary stages. The ability to deduce the ages of stars with a relative precision of typically 10 to 20% is a unique opportunity for stellar evolution and also of great value for both galactic and exoplanet studies. Further, a major uncalibrated ingredient that makes stellar evolution models uncertain, is the stellar interior rotation frequency $\\Omega(r)$ and its evolution during stellar life. We summarize the recent achievements in the derivation of $\\Omega(r)$ for different types stars, offering stringent observational constraints on theoretical models. Core-to-envelope rotation rates during the red giant stage are far lower than theoretical predictions, pointing towards the need to include new physical ingredients that allow strong and efficient coupling between the core and the envelope in the models of low-mass stars in the evolutionary phase prior to the core helium burning. Stars ...

  1. Dual annular rotating "windowed" nuclear reflector reactor control system

    DOE Patents [OSTI]

    Jacox, Michael G. (Idaho Falls, ID); Drexler, Robert L. (Idaho Falls, ID); Hunt, Robert N. M. (Idaho Falls, ID); Lake, James A. (Idaho Falls, ID)

    1994-01-01T23:59:59.000Z

    A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core.

  2. Possible Measurable Effects of Dark Energy in Rotating Superconductors

    E-Print Network [OSTI]

    Clovis Jacinto de Matos; Christian Beck

    2007-07-12T23:59:59.000Z

    We discuss recent laboratory experiments with rotating superconductors and show that three so far unexplained experimentally observed effects (anomalous acceleration signals, anomalous gyroscope signals, Cooper pair mass excess) can be physically explained in terms of a possible interaction of dark energy with Cooper pairs. Our approach is based on a Ginzburg-Landau-like model of electromagnetic dark energy, where gravitationally active photons obtain mass in the superconductor. We show that this model can account simultaneously for the anomalous acceleration and anomalous gravitomagnetic fields around rotating superconductors measured by Tajmar et al. and for the anomalous Cooper pair mass in superconductive Niobium, measured by Cabrera and Tate. It is argued that these three different physical effects are ultimately different experimental manifestations of the simultaneous spontaneous breaking of gauge invariance, and of the principle of general covariance in superconductive materials.

  3. Rotational quenching of CO due to H$_2$ collisions

    E-Print Network [OSTI]

    Yang, Benhui; Balakrishnan, N; Forrey, R C

    2010-01-01T23:59:59.000Z

    Rate coefficients for state-to-state rotational transitions in CO induced by both para- and ortho-H$_2$ collisions are presented. The results were obtained using the close-coupling method and the coupled-states approximation, with the CO-H$_2$ interaction potential of Jankowski & Szalewicz (2005). Rate coefficients are presented for temperatures between 1 and 3000 K, and for CO($v=0,j$) quenching from $j=1-40$ to all lower $j^\\prime$ levels. Comparisons with previous calculations using an earlier potential show some discrepancies, especially at low temperatures and for rotational transitions involving large $|\\Delta j|$. The differences in the well depths of the van der Waals interactions in the two potential surfaces lead to different resonance structures in the energy dependence of the cross sections which influence the low temperature rate coefficients. Applications to far infrared observations of astrophysical environments are briefly discussed.

  4. Cooling Flows of Self-Gravitating, Rotating, Viscous Systems

    E-Print Network [OSTI]

    Mohsen Shadmehri; Jamshid Ghanbari

    2002-04-06T23:59:59.000Z

    We obtain self-similar solutions that describe the dynamics of a self-gravitating, rotating, viscous system. We use simplifying assumptions; but explicitly include viscosity and the cooling due to the dissipation of energy. By assuming that the turbulent dissipation of energy is as power law of the density and the speed v_{rms} and for a power-law dependence of viscosity on the density, pressure, and rotational velocity, we investigate turbulent cooling flows. It has been shown that for the cylindrically and the spherically cooling flows the similarity indices are the same, and they depend only on the exponents of the dissipation rate and the viscosity model. Depending on the values of the exponents, which the mechanisms of the dissipation and viscosity determine them, we may have solutions with different general physical properties. The conservation of the total mass and the angular momentum of the system strongly depends on the mechanisms of energy dissipation and the viscosity model.

  5. Prototype Spallation Neutron Source Rotating Target Assembly Final Test Report

    SciTech Connect (OSTI)

    McManamy, Thomas J [ORNL; Graves, Van [Oak Ridge National Laboratory (ORNL); Garmendia, Amaia Zarraoa [IDOM Bilbao; Sorda, Fernando [ESS Bilbao; Etxeita, Borja [IDOM Bilbao; Rennich, Mark J [ORNL

    2011-01-01T23:59:59.000Z

    A full-scale prototype of an extended vertical shaft, rotating target assembly based on a conceptual target design for a 1 to 3-MW spallation facility was built and tested. Key elements of the drive/coupling assembly implemented in the prototype include high integrity dynamic face seals, commercially available bearings, realistic manufacturing tolerances, effective monitoring and controls, and fail-safe shutdown features. A representative target disk suspended on a 3.5 meter prototypical shaft was coupled with the drive to complete the mechanical tests. Successful operation for 5400 hours confirmed the overall mechanical feasibility of the extended vertical shaft rotating target concept. The prototype system showed no indications of performance deterioration and the equipment did not require maintenance or relubrication.

  6. PIC simulation of electrodeless plasma thruster with rotating electric field

    SciTech Connect (OSTI)

    Nomura, Ryosuke; Ohnishi, Naofumi; Nishida, Hiroyuki [Department of Aerospace Engineering, Tohoku University, Sendai 980-8579 (Japan); Department of Mechanical Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo 184-8588 (Japan)

    2012-11-27T23:59:59.000Z

    For longer lifetime of electric propulsion system, an electrodeless plasma thruster with rotating electric field have been proposed utilizing a helicon plasma source. The rotating electric field may produce so-called Lissajous acceleration of helicon plasma in the presence of diverging magnetic field through a complicated mechanism originating from many parameters. Two-dimensional simulations of the Lissajous acceleration were conducted by a code based on Particle-In-Cell (PIC) method and Monte Carlo Collision (MCC) method for understanding plasma motion in acceleration area and for finding the optimal condition. Obtained results show that azimuthal current depends on ratio of electron drift radius to plasma region length, AC frequency, and axial magnetic field. When ratio of cyclotron frequency to the AC frequency is higher than unity, reduction of the azimuthal current by collision effect is little or nothing.

  7. Dissipative dark matter and the rotation curves of dwarf galaxies

    E-Print Network [OSTI]

    Foot, R

    2015-01-01T23:59:59.000Z

    There is ample evidence from rotation curves that dark matter halo's around disk galaxies have nontrivial dynamics. Of particular significance are: a) the cored dark matter profile of disk galaxies, b) correlations of the shape of rotation curves with baryonic properties, and c) the Tully-Fisher relation. Dark matter halo's around disk galaxies may have nontrivial dynamics if dark matter is strongly self interacting and dissipative. Multicomponent hidden sector dark matter featuring a massless `dark photon' (from an unbroken dark $U(1)$ gauge interaction) which kinetically mixes with the ordinary photon provides a concrete example of such dark matter. The kinetic mixing interaction facilitates halo heating by enabling ordinary supernovae to be a source of these `dark photons'. Dark matter halo's can expand and contract in response to the heating and cooling processes, but for a sufficiently isolated halo should have evolved to a steady state or `equilibrium' configuration where heating and cooling rates local...

  8. Rotating BTZ Black Holes and One Dimensional Holographic Superconductors

    E-Print Network [OSTI]

    Pankaj Chaturvedi; Gautam Sengupta

    2014-06-30T23:59:59.000Z

    We consider charged rotating BTZ black holes in 2+1 dimensions and obtain 1+1 dimensional holographic superconductors on a spatial circle in the context of the $AdS_3/CFT_2$ correspondence. The charged condensate for the boundary superconductor is computed both in the analytic and the numerical framework in a probe limit and a low angular momentum approximation. A critical value of the angular momentum for the onset of superconductivity is established. We also numerically compute the electrical conductivity of the 1+1 dimensional boundary theory on a circle. The conductivity exhibits a dependence on angular momentum of the rotating black hole both for the normal and the superconducting phase of the boundary field theory. The significance of the boundary field theory in the context of a Fermi-Luttinger liquid on a circle is discussed.

  9. On the black hole limit of rotating discs and rings

    E-Print Network [OSTI]

    Andreas Kleinwächter; Hendrick Labranche; Reinhard Meinel

    2010-07-20T23:59:59.000Z

    Solutions to Einstein's field equations describing rotating fluid bodies in equilibrium permit parametric (i.e. quasi-stationary) transitions to the extreme Kerr solution (outside the horizon). This has been shown analytically for discs of dust and numerically for ring solutions with various equations of state. From the exterior point of view, this transition can be interpreted as a (quasi) black hole limit. All gravitational multipole moments assume precisely the values of an extremal Kerr black hole in the limit. In the present paper, the way in which the black hole limit is approached is investigated in more detail by means of a parametric Taylor series expansion of the exact solution describing a rigidly rotating disc of dust. Combined with numerical calculations for ring solutions our results indicate an interesting universal behaviour of the multipole moments near the black hole limit.

  10. A high precision, compact electromechanical ground rotation sensor

    SciTech Connect (OSTI)

    Dergachev, V., E-mail: volodya@caltech.edu [LIGO Laboratory, California Institute of Technology, MS 100-36, Pasadena, California 91125 (United States); DeSalvo, R. [LIGO Laboratory, California Institute of Technology, MS 100-36, Pasadena, California 91125 (United States) [LIGO Laboratory, California Institute of Technology, MS 100-36, Pasadena, California 91125 (United States); University of Sannio, C.so Garibaldi 107, Benevento 82100 (Italy); Asadoor, M. [Mayfield Senior School, 500 Bellefontaine Street, Pasadena, California 91105 (United States) [Mayfield Senior School, 500 Bellefontaine Street, Pasadena, California 91105 (United States); Oklahoma State University, 219 Student Union, Stillwater, Oklahoma 74074 (United States); Bhawal, A. [Arcadia High School, 180 Campus Drive, Arcadia, California 91007 (United States) [Arcadia High School, 180 Campus Drive, Arcadia, California 91007 (United States); Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Gong, P. [Department of Precision Instrument, Tsinghua University, Beijing 100084 (China) [Department of Precision Instrument, Tsinghua University, Beijing 100084 (China); School of Industrial and System Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0205 (United States); Kim, C. [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States); Lottarini, A. [Department of Computer Science, University of Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy) [Department of Computer Science, University of Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Department of Computer Science, Columbia University, 1214 Amsterdam Avenue, New York, New York 10027 (United States); Minenkov, Y. [Sezione INFN Tor Vergata, via della Ricerca Scientifica  1, 00133 Roma (Italy)] [Sezione INFN Tor Vergata, via della Ricerca Scientifica  1, 00133 Roma (Italy); Murphy, C. [School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, Western Australia 6009 (Australia) [School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, Western Australia 6009 (Australia); University of Melbourne Grattan Street, Parkville VIC 3010 (Australia); O'Toole, A. [University of California, Los Angeles, 405 Hilgard Ave, Los Angeles, California 90095 (United States) [University of California, Los Angeles, 405 Hilgard Ave, Los Angeles, California 90095 (United States); Michigan Technological University, 1400 Townsend Dr, Houghton, Michigan 49931 (United States); Peña Arellano, F. E. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); and others

    2014-05-15T23:59:59.000Z

    We present a mechanical rotation sensor consisting of a balance pivoting on a tungsten carbide knife edge. These sensors are important for precision seismic isolation systems, as employed in land-based gravitational wave interferometers and for the new field of rotational seismology. The position sensor used is an air-core linear variable differential transformer with a demonstrated noise floor of 1 × 10{sup ?11}m/?( Hz ). We describe the instrument construction and demonstrate low noise operation with a noise floor upper bound of 5.7 × 10{sup ?9} rad /?( Hz ) at 10 mHz and 6.4 × 10{sup ?10} rad /?( Hz ) at 0.1 Hz. The performance of the knife edge hinge is compatible with a behaviorur free of noise from dislocation self-organized criticality.

  11. What is the optimum stellar rotation rate for a collapsar?

    E-Print Network [OSTI]

    William H. Lee

    2007-03-01T23:59:59.000Z

    We consider low angular momentum, neutrino cooled accretion flows onto newborn black holes in the context of the collapsar model for long Gamma Ray Bursts, and find a considerable energy release for rotation rates lower than those usually considered. The efficiency for the transformation of gravitational binding energy into radiation is maximized when the equatorial angular momentum l0 ~ 2 Rg c, where Rg is the Schwarzschild radius.

  12. Anisotropic Bianchi types VIII and IX locally rotationally symmetric cosmologies

    SciTech Connect (OSTI)

    Assad, M.J.D.; Soares, I.D.

    1983-10-15T23:59:59.000Z

    We present a class of exact cosmological solutions of Einstein-Maxwell equations, which are anisotropic and spatially homogeneous of Bianchi types VIII and IX, and class IIIb in the Stewart-Ellis classification of locally rotationally symmetric models. If we take the electromagnetic field equal to zero, a class of Bianchi types VIII/IX spatially homogeneous anisotropic cosmological solutions with perfect fluid is obtained.

  13. Seismic diagnostics for transport of angular momentum in stars 2. Interpreting observed rotational splittings of slowly-rotating red giant stars

    E-Print Network [OSTI]

    Goupil, M J; Marques, J P; Ouazzani, R M; Belkacem, K; Lebreton, Y; Samadi, R

    2012-01-01T23:59:59.000Z

    Asteroseismology with the space-borne missions CoRoT and Kepler provides a powerful mean of testing the modeling of transport processes in stars. Rotational splittings are currently measured for a large number of red giant stars and can provide stringent constraints on the rotation profiles. The aim of this paper is to obtain a theoretical framework for understanding the properties of the observed rotational splittings of red giant stars with slowly rotating cores. This allows us to establish appropriate seismic diagnostics for rotation of these evolved stars. Rotational splittings for stochastically excited dipolar modes are computed adopting a first-order perturbative approach for two $1.3 M_\\odot$ benchmark models assuming slowly rotating cores. For red giant stars with slowly rotating cores, we show that the variation of the rotational splittings of $\\ell=1$ modes with frequency depends only on the large frequency separation, the g-mode period spacing, and the ratio of the average envelope to core rotatio...

  14. Resonant Interactions in Rotating Homogeneous Three-dimensional Turbulence

    E-Print Network [OSTI]

    Q. Chen; S. Chen; G. L. Eyink; D. D. Holm

    2004-04-29T23:59:59.000Z

    Direct numerical simulations of three-dimensional (3D) homogeneous turbulence under rapid rigid rotation are conducted to examine the predictions of resonant wave theory for both small Rossby number and large Reynolds number. The simulation results reveal that there is a clear inverse energy cascade to the large scales, as predicted by 2D Navier-Stokes equations for resonant interactions of slow modes. As the rotation rate increases, the vertically-averaged horizontal velocity field from 3D Navier-Stokes converges to the velocity field from 2D Navier-Stokes, as measured by the energy in their difference field. Likewise, the vertically-averaged vertical velocity from 3D Navier-Stokes converges to a solution of the 2D passive scalar equation. The energy flux directly into small wave numbers in the $k_z=0$ plane from non-resonant interactions decreases, while fast-mode energy concentrates closer to that plane. The simulations are consistent with an increasingly dominant role of resonant triads for more rapid rotation.

  15. SOLAR ROTATION RATE DURING THE CYCLE 24 MINIMUM IN ACTIVITY

    SciTech Connect (OSTI)

    Antia, H. M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Basu, Sarbani, E-mail: antia@tifr.res.i, E-mail: sarbani.basu@yale.ed [Department of Astronomy, Yale University, P.O. Box 208101, New Haven CT 06520-8101 (United States)

    2010-09-01T23:59:59.000Z

    The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We find that the band of fast rotating region close to the equator bifurcated around 2005 and recombined by 2008. This behavior is different from that during the cycle 23 minimum. By autocorrelating the zonal-flow pattern with a time shift, we find that in terms of solar dynamics, solar cycle 23 lasted for a period of 11.7 years, consistent with the result of Howe et al. (2009). The autocorrelation coefficient also confirms that the zonal-flow pattern penetrates through the convection zone.

  16. Large-scale anisotropy in stably stratified rotating flows

    SciTech Connect (OSTI)

    Marino, Dr. Raffaele [National Center for Atmospheric Research (NCAR); Mininni, Dr. Pablo D. [Universidad de Buenos Aires, Argentina; Rosenberg, Duane L [ORNL; Pouquet, Dr. Annick [National Center for Atmospheric Research (NCAR)

    2014-01-01T23:59:59.000Z

    We present results from direct numerical simulations of the Boussinesq equations in the presence of rotation and/or stratification, both in the vertical direction. The runs are forced isotropically and randomly at small scales and have spatial resolutions of up to $1024^3$ grid points and Reynolds numbers of $\\approx 1000$. We first show that solutions with negative energy flux and inverse cascades develop in rotating turbulence, whether or not stratification is present. However, the purely stratified case is characterized instead by an early-time, highly anisotropic transfer to large scales with almost zero net isotropic energy flux. This is consistent with previous studies that observed the development of vertically sheared horizontal winds, although only at substantially later times. However, and unlike previous works, when sufficient scale separation is allowed between the forcing scale and the domain size, the total energy displays a perpendicular (horizontal) spectrum with power law behavior compatible with $\\sim k_\\perp^{-5/3}$, including in the absence of rotation. In this latter purely stratified case, such a spectrum is the result of a direct cascade of the energy contained in the large-scale horizontal wind, as is evidenced by a strong positive flux of energy in the parallel direction at all scales including the largest resolved scales.

  17. A nonlinear calculation of rotating cavitation in inducers

    SciTech Connect (OSTI)

    Tsujimoto, Y.; Watanabe, S.; Yoshida, Y. [Osaka Univ., Osaka (Japan); Kamijo, K. [Kakuda Research Center (Japan). Rocket Propulsion Division

    1994-12-31T23:59:59.000Z

    In the previous linear analysis (Tsujimoto et al., 1993) it was found that there can be a backward rotating cavitation as well as a forward mode which rotates faster than impeller. Although some shaft vibration has been observed which might be caused by the backward mode, experimental evidence has been obtained only for the forward mode. The ultimate goal of the present study is to answer the question which mode of the cavitation instabilities -- cavitation surge and the two modes of rotating cavitation -- occurs in a given system and operating condition, and to find out analytical method to determine their amplitude. A time marching non-linear 2-D flow analysis was carried out for this purpose. It was found that the increase of cavitation compliance at lower inlet pressure can be a factor which limits the amplitude. The mode selectivity is mainly dependent on the stability limit obtained by a linear analysis for which the phase delay of cavity has a most important effect.

  18. Wind Circulation in Selected Rotating Magnetic Early-B Stars

    E-Print Network [OSTI]

    Myron A. Smith; Detlef Groote

    2001-04-03T23:59:59.000Z

    The rotating magnetic B stars have oblique dipolar magnetic fields and often anomalous helium and metallic compositions. These stars develop co-rotating torus-shaped clouds by channelling winds from their magnetic poles to an anchored planar disk over the magnetic equator. The line absorptions from the cloud can be studied as the complex rotates and periodically occults the star. We describe an analysis of the clouds of four stars (HD184927, beta Cep, sigma Ori E, and HR6684). From line synthesis models, we find that the metallic compositions are spatially uniform over the stars' surfaces. Next, using the Hubeny CIRCUS code, we demonstate that periodic UV continuum fluxes can be explained by the absorption of low-excitation lines. The analysis also quantifies the cloud temperatures, densities, and turbulences, which appear to increase inward toward the stars. The temperatures range from about 12,000K for the weak Fe lines up to temperatures of 33,000K for N V absorptions, which is in excess of temperatures expected from radiative equilibrium. The spectroscopic hallmark of this stellar class is the presence of strong C IV and N V resonance line absorptions at occultation phases and of redshifted emissions at magnetic pole-on phases. The emissions have characteristics which seem most compatible with the generation of high-energy shocks at the wind-cloud interface, as predicted by Babel.

  19. Fiber-Optic-Gyroscope Measurements Close to Rotating Liquid Helium

    E-Print Network [OSTI]

    M. Tajmar; F. Plesescu

    2009-11-05T23:59:59.000Z

    We previously reported anomalous fiber-optic gyroscope signals observed above rotating rings at temperatures close to liquid helium. Our results suggested that the liquid helium itself may be the source of our observed phenomenon. We constructed a new cryostat experiment that allows rotating a large quantity of liquid helium together with a superconducting niobium tube. The facility is built in such a way that our gyroscope can be placed directly in the center of rotation along the axis; however, the cryostat is built around the gyroscope to allow measuring without interference of helium liquid or gas. An anomalous signal was found of similar value compared to our previous measurements with a changed sign. As this measurement was done at a different location (center position) with respect to our old setup (top position), first hints for a possible field distribution of this phenomenon can be made. However, due to lower angular velocities used in this new setup so far, our measurement resolution was close to three times the resolution of our gyroscope and hence our data represent work in progress.

  20. Particle acceleration in rotating and shearing jets from AGN

    E-Print Network [OSTI]

    F. M. Rieger; K. Mannheim

    2002-10-14T23:59:59.000Z

    We model the acceleration of energetic particles due to shear and centrifugal effects in rotating astrophysical jets. The appropriate equation describing the diffusive transport of energetic particles in a collisionless, rotating background flow is derived and analytical steady state solutions are discussed. In particular, by considering velocity profiles from rigid, over flat to Keplerian rotation, the effects of centrifugal and shear acceleration of particles scattered by magnetic inhomogeneities are distinguished. In the case where shear acceleration dominates, it is confirmed that power law particle momentum solutions $f(p) \\propto p^{-(3+\\alpha)}$ exist, if the mean scattering time $\\tau_c \\propto p^{\\alpha}$ is an increasing function of momentum. We show that for a more complex interplay between shear and centrifugal acceleration, the recovered power law momentum spectra might be significantly steeper but flatten with increasing azimuthal velocity due to the increasing centrifugal effects. The possible relevance of shear and centrifugal acceleration for the observed extended emission in AGN is demonstrated for the case of the jet in the quasar 3C273.

  1. Braking index of isolated uniformly rotating magnetized pulsars

    E-Print Network [OSTI]

    Hamil, Oliver; Urbanec, Martin; Urbancova, Gabriela

    2015-01-01T23:59:59.000Z

    Isolated pulsars are rotating neutron stars with accurately measured angular velocities $\\Omega$, and their time derivatives which show unambiguously that the pulsars are slowing down. Although the exact mechanism of the spin-down is a question of debate in detail, the commonly accepted view is that it arises through emission of magnetic dipole radiation (MDR) from a rotating magnetized body. Other processes, including the emission of gravitational radiation, and of relativistic particles (pulsar wind), are also being considered. The calculated energy loss by a rotating pulsar with a constant moment of inertia is assumed proportional to a model dependent power of $\\Omega$. This relation leads to the power law $\\dot{\\Omega}$ = -K $\\Omega^{\\rm n}$ where $n$ is called the braking index. The MDR model predicts $n$ exactly equal to 3. Selected observations of isolated pulsars provide rather precise values of $n$, individually accurate to a few percent or better, in the range 1$ <$ n $ < $ 2.8, which is consi...

  2. Inhomogeneous Vortex Patterns in Rotating Bose-Einstein Condensates

    E-Print Network [OSTI]

    Correggi, Michele

    2012-01-01T23:59:59.000Z

    We consider a 2D rotating Bose gas described by the Gross-Pitaevskii (GP) theory and investigate the properties of the ground state of the theory for rotational speeds close to the critical speed for vortex nucleation. While one could expect that the vortex distribution should be homogeneous within the condensate we prove by means of an asymptotic analysis in the strongly interacting (Thomas-Fermi) regime that it is not. More precisely we rigorously derive a formula due to Sheehy and Radzihovsky [Phys. Rev. A 70, 063620(R) (2004)] for the vortex distribution, a consequence of which is that the vortex distribution is strongly inhomogeneous close to the critical speed and gradually homogeneizes when the rotation speed is increased. From the mathematical point of view, a novelty of our approach is that we do not use any compactness argument in the proof, but instead provide explicit estimates on the difference between the vorticity measure of the GP ground state and the minimizer of a certain renormalized energy...

  3. Investigating the point seismic array concept with seismic rotation measurements.

    SciTech Connect (OSTI)

    Abbott, Robert E.; Aldridge, David Franklin

    2009-02-01T23:59:59.000Z

    Spatially-distributed arrays of seismometers are often utilized to infer the speed and direction of incident seismic waves. Conventionally, individual seismometers of the array measure one or more orthogonal components of rectilinear particle motion (displacement, velocity, or acceleration). The present work demonstrates that measure of both the particle velocity vector and the particle rotation vector at a single point receiver yields sufficient information to discern the type (compressional or shear), speed, and direction of an incident plane seismic wave. Hence, the approach offers the intriguing possibility of dispensing with spatially-extended received arrays, with their many problematic deployment, maintenance, relocation, and post-acquisition data processing issues. This study outlines straightforward mathematical theory underlying the point seismic array concept, and implements a simple cross-correlation scanning algorithm for determining the azimuth of incident seismic waves from measured acceleration and rotation rate data. The algorithm is successfully applied to synthetic seismic data generated by an advanced finite-difference seismic wave propagation modeling algorithm. Application of the same azimuth scanning approach to data acquired at a site near Yucca Mountain, Nevada yields ambiguous, albeit encouraging, results. Practical issues associated with rotational seismometry are recognized as important, but are not addressed in this investigation.

  4. CONFRONTING COLD DARK MATTER PREDICTIONS WITH OBSERVED GALAXY ROTATIONS

    SciTech Connect (OSTI)

    Obreschkow, Danail; Meyer, Martin; Power, Chris; Staveley-Smith, Lister [International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009 (Australia)] [International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009 (Australia); Ma, Xiangcheng [The University of Sciences and Technology of China, Centre for Astrophysics, Hefei, Anhui 230026 (China)] [The University of Sciences and Technology of China, Centre for Astrophysics, Hefei, Anhui 230026 (China); Zwaan, Martin [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching b. Muenchen (Germany)] [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching b. Muenchen (Germany); Drinkwater, Michael J. [School of Mathematics and Physics, The University of Queensland, Brisbane, QLD 4072 (Australia)] [School of Mathematics and Physics, The University of Queensland, Brisbane, QLD 4072 (Australia)

    2013-04-01T23:59:59.000Z

    The rich statistics of galaxy rotations as captured by the velocity function (VF) provide invaluable constraints on galactic baryon physics and the nature of dark matter (DM). However, the comparison of observed galaxy rotations against cosmological models is prone to subtle caveats that can easily lead to misinterpretations. Our analysis reveals full statistical consistency between {approx}5000 galaxy rotations, observed in line-of-sight projection, and predictions based on the standard cosmological model ({Lambda}CDM) at the mass-resolution of the Millennium simulation (H I line-based circular velocities above {approx}50 km s{sup -1}). Explicitly, the H I linewidths in the H I Parkes All Sky Survey (HIPASS) are found to be consistent with those in S{sup 3}-SAX, a post-processed semi-analytic model for the Millennium simulation. Previously found anomalies in the VF can be plausibly attributed to (1) the mass-limit of the Millennium simulation, (2) confused sources in HIPASS, (3) inaccurate inclination measurements for optically faint sources, and (4) the non-detectability of gas-poor early-type galaxies. These issues can be bypassed by comparing observations and models using linewidth source counts rather than VFs. We investigate if and how well such source counts can constrain the temperature of DM.

  5. Seismic modelling of the rotating, slowly pulsating B-type star HD 21071

    E-Print Network [OSTI]

    Szewczuk, Wojciech

    2015-01-01T23:59:59.000Z

    Interpretation of the oscillation spectrum of the slowly pulsating B-type star HD21071 is presented. We show that non-rotating models cannot account for the two highest amplitude frequencies and taking into account the effects of rotation is necessary. Rotating seismic models are constructed using various chemical compositions, opacity data, core overshooting parameters and rotational velocities. There are prospects for seismic modelling of SPB stars, even if no asymptotic pattern is observed in their oscillation spectra, provided an unambiguous mode identification is doable and the effects of rotation are properly included.

  6. Fermi coordinates and modified Franklin transformation : A comparative study on rotational phenomena

    E-Print Network [OSTI]

    M. Nouri-Zonoz; H. Ramezani-Aval

    2014-12-18T23:59:59.000Z

    Employing a relativistic rotational transformation to study and analyze rotational phenomena, instead of the rotational transformations based on consecutive Lorentz transformations and Fermi coordinates, leads to different predictions. In this article, after a comparative study between Fermi metric of a uniformly rotating eccentric observer and the spacetime metric in the same observer's frame obtained through the modified Franklin transformation, we consider rotational phenomena including transverse Doppler effect and Sagnac effect in both formalisms and compare their predictions. We also discuss length measurements in the two formalisms.

  7. Emergence of rotational bands in ab initio no-core configuration interaction calculations

    E-Print Network [OSTI]

    M. A. Caprio; P. Maris; J. P. Vary; R. Smith

    2015-02-04T23:59:59.000Z

    Rotational bands have been observed to emerge in ab initio no-core configuration interaction (NCCI) calculations for p-shell nuclei, as evidenced by rotational patterns for excitation energies, electromagnetic moments, and electromagnetic transitions. We investigate the ab initio emergence of nuclear rotation in the Be isotopes, focusing on 9Be for illustration, and make use of basis extrapolation methods to obtain ab initio predictions of rotational band parameters for comparison with experiment. We find robust signatures for rotational motion, which reproduce both qualitative and quantitative features of the experimentally observed bands.

  8. Quantum Calculation of Inelastic CO Collisions with H: I. rotational quenching of low-lying rotational levels

    E-Print Network [OSTI]

    Yang, Benhui; Balakrishnan, N; Forrey, R C; Bowman, J M

    2013-01-01T23:59:59.000Z

    New quantum scattering calculations for rotational deexcitation transitions of CO induced by H collisions using two CO-H potential energy surfaces (PESs) from Shepler et al. (2007) are reported. State-to-state rate coefficients are computed for temperatures ranging from 1 to 3000 K for CO($v=0,j$) deexcitation from $j=1-5$ to all lower $j^\\prime$ levels, with $j$ being the rotational quantum number. Different resonance structures in the cross sections are attributed to the differences in the anisotropy and the long-range van der Waals well depths of the two PESs. These differences affect rate coefficients at low temperatures and give an indication of the uncertainty of the results. Significant discrepancies are found between the current rate coefficients and previous results computed using earlier potentials, while the current results satisfy expected propensity rules. Astrophysical applications to modeling far infrared and submillimeter observations are briefly discussed.

  9. The Dosimetric Impact of Prostate Rotations During Electromagnetically Guided External-Beam Radiation Therapy

    SciTech Connect (OSTI)

    Amro, Hanan, E-mail: hanan.amro@gmail.com [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Hamstra, Daniel A.; Mcshan, Daniel L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Sandler, Howard [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States)] [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States); Vineberg, Karen; Hadley, Scott; Litzenberg, Dale [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-01-01T23:59:59.000Z

    Purpose: To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials: Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D{sub 95} and V{sub 79} were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results: Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions: Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.

  10. Stationary Axisymmetric and Slowly Rotating Spacetimes in Ho?ava-Lifshitz Gravity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Anzhong

    2013-02-01T23:59:59.000Z

    Stationary, axisymmetric, and slowly rotating vacuum spacetimes in the Horava-Lifshitz (HL) gravity are studied, and it is shown that, for any given spherical static vacuum solution of the HL theory (of any model, including the ones with an additional U(1) symmetry), there always exists a corresponding slowly rotating, stationary, and axisymmetric vacuum solution, which reduces to the former, when the rotation is switched off. The rotation is universal and only implicitly depends on the models of the HL theory and their coupling constants through the spherical seed solution. As a result, all asymptotically flat slowly rotating vacuum solutions are asymptotically identical to the slowly rotating Kerr solution. This is in contrast to the claim of Barausse and Sotiriou [Phys. Rev. Lett. 109, 181101 (2012)], in which slowly rotating black holes were reported (incorrectly) not to exist in the infrared limit of the nonprojectable HL theory.

  11. Integrated Study of MFRSR-derived Parameters of Atmospheric Aerosols and Trace Gases Over the ARM CART Site Extended Facili...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other NewsSpin andInterim Data

  12. E.-H. HALL. 2014 On the rotational Coefficient in nickel and cobalt ( Coefficients de rotation du nickel et du cobalt); Philosophical Magazine, 5e srie, t. XII.

    E-Print Network [OSTI]

    Boyer, Edmond

    509 E.-H. HALL. 2014 On the « rotational Coefficient in nickel and cobalt » ( Coefficients de rotation du nickel et du cobalt); Philosophical Magazine, 5e série, t. XII. p. 157; 1881. E.-H. HALL. 2014 pour le fer, le nickel, l'argent, l'or, le cobalt, l'aluminium, le magnésium; l'effet est bien moindre

  13. Partial rotational lattice order–disorder in stefin B crystals

    SciTech Connect (OSTI)

    Renko, Miha [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Taler-Ver?i?, Ajda [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Miheli?, Marko [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Žerovnik, Eva [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Turk, Dušan, E-mail: dusan.turk@ijs.si [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia)

    2014-04-01T23:59:59.000Z

    Crystal lattice disorders are a phenomenon which may hamper the determination of macromolecular crystal structures. Using the case of the crystal structure of stefin B, identification of rotational order–disorder and structure determination are described. At present, the determination of crystal structures from data that have been acquired from twinned crystals is routine; however, with the increasing number of crystal structures additional crystal lattice disorders are being discovered. Here, a previously undescribed partial rotational order–disorder that has been observed in crystals of stefin B is described. The diffraction images revealed normal diffraction patterns that result from a regular crystal lattice. The data could be processed in space groups I4 and I422, yet one crystal exhibited a notable rejection rate in the higher symmetry space group. An explanation for this behaviour was found once the crystal structures had been solved and refined and the electron-density maps had been inspected. The lattice of stefin B crystals is composed of five tetramer layers: four well ordered layers which are followed by an additional layer of alternatively placed tetramers. The presence of alternative positions was revealed by the inspection of electron-density score maps. The well ordered layers correspond to the crystal symmetry of space group I422. In addition, the positions of the molecules in the additional layer are related by twofold rotational axes which correspond to space group I422; however, these molecules lie on the twofold axis and can only be related in a statistical manner. When the occupancies of alternate positions and overlapping are equal, the crystal lattice indeed fulfills the criteria of space group I422; when these occupancies are not equal, the lattice only fulfills the criteria of space group I4.

  14. Rotation, Statistical Dynamics and Kinematics of Globular Clusters

    E-Print Network [OSTI]

    Donald Lynden-Bell

    2000-07-10T23:59:59.000Z

    Evolution with mass segregation and the evolution of the rotation of cores are both discussed for self-similar core collapse. Evolution with angular velocity proportional to the square root of the density is predicted. On the Dynamical Main Sequence of globular clusters the energy emission from binaries balances the energy expended in expanding the halo. Newton's exactly solved N-body problem is then given, along with recent generalisations, all of which have no violent relaxation, but a new type of statistical equilibrium is discussed. Finally, we set the creation of streams in the Galaxy's halo in the historical context of their discovery.

  15. Plasma Frequency Shift Due to a Slowly Rotating Compact Star

    E-Print Network [OSTI]

    Babur M. Mirza; Hamid Saleem

    2005-05-10T23:59:59.000Z

    We investigate the effects of a slowly rotating compact gravitational source on electron oscillations in a homogeneous electrically neutral plasma in the absence of an external electric or magnetic field. Neglecting the random thermal motion of the electrons we assume the gravitoelectromagnetic approximation to the general theory of relativity for the gravitational field. It is shown that there is a shift in the plasma frequency and hence in the dielectric constant of the plasma due to the gravitomagnetic force. We also give estimates for the difference in the frequency of radially transmitted electromagnetic signals for typical compact star candidates.

  16. Stator for a rotating electrical machine having multiple control windings

    DOE Patents [OSTI]

    Shah, Manoj R. (Latham, NY); Lewandowski, Chad R. (Amsterdam, NY)

    2001-07-17T23:59:59.000Z

    A rotating electric machine is provided which includes multiple independent control windings for compensating for rotor imbalances and for levitating/centering the rotor. The multiple independent control windings are placed at different axial locations along the rotor to oppose forces created by imbalances at different axial locations along the rotor. The multiple control windings can also be used to levitate/center the rotor with a relatively small magnetic field per unit area since the rotor and/or the main power winding provides the bias field.

  17. Control coil arrangement for a rotating machine rotor

    DOE Patents [OSTI]

    Shah, Manoj R. (Latham, NY); Lewandowsk, Chad R. (Amsterdam, NY)

    2001-07-31T23:59:59.000Z

    A rotating machine (e.g., a turbine, motor or generator) is provided wherein a fixed solenoid or other coil configuration is disposed adjacent to one or both ends of the active portion of the machine rotor for producing an axially directed flux in the active portion so as to provide planar axial control at single or multiple locations for rotor balance, levitation, centering, torque and thrust action. Permanent magnets can be used to produce an axial bias magnetic field. The rotor can include magnetic disks disposed in opposed, facing relation to the coil configuration.

  18. Nonlinear magneto-optic polarization rotation with intense laser fields

    E-Print Network [OSTI]

    Hsu, Paul S.; Patnaik, Anil K.; Welch, George R.

    2008-01-01T23:59:59.000Z

    spectroscopy measurements #3;1,2#4;, both for fun- damental and practical reasons such as optical magnetometry #3;3#4;. The sensitivity of optical pumping magnetometers #1;OPMs#2; has already achieved 10?9 G /#5;Hz under laboratory conditions #3...;4,5#4;. Also, nonlinear magneto-optic rotation has been used in magnetometry to reach very high sensitivity #3;6#4;. In such devices, the Zeeman level shift measurements are based on light absorption #3;7#4;, but the sensitivity is limited if the absorption...

  19. Quantum-information approach to rotating Bose-Einstein condensates

    SciTech Connect (OSTI)

    Liu Zhao; Guo Hongli; Chen Shu; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2009-12-15T23:59:59.000Z

    We investigate the two-dimensional weakly interacting rotating Bose-Einstein condensate by the tools of quantum information theory. The critical exponents of the ground-state fidelity susceptibility and the correlation length of the system are obtained for the sudden change of the ground state when the first vortex is formed. This sudden change can also be indicated by the ground state entanglement. We also find the single-particle entanglement can be an indicator of the angular momentums for some real ground states. The single-particle entanglement of fractional quantum Hall states such as Laughlin state and Pfaffian state is also studied.

  20. Gamma N Delta Form Factors and Wigner Rotations

    E-Print Network [OSTI]

    Milton Dean Slaughter

    2008-10-28T23:59:59.000Z

    For more than 50 years the Delta N gamma form factors have been studied experimentally, theoretically, and phenomenologically. Although there has been substantial progress in understanding their behavior, there remains much work to be done. A major tool used in many investigations is the Jones-Scadron Delta rest frame parametrization of the three Delta N gamma form factors. We point out that many studies utilizing this parametrization may not account for Wigner rotations and the consequent helicity mixing that ensues when the Delta is not at rest.

  1. Gravitational collapse with rotating thin shells and cosmic censorship

    E-Print Network [OSTI]

    Jorge V. Rocha

    2015-03-17T23:59:59.000Z

    Gravitational collapse of matter in the presence of rotation is a mostly unexplored topic but it might have important implications for cosmic censorship. Recently a convenient setup was identified to address this problem, by considering thin matter shells at the interface between two equal angular momenta Myers-Perry spacetimes in five dimensions. This note provides more details about the matching of such cohomogeneity-1 spacetimes and extends the results obtained therein to arbitrary higher odd dimensions. It is also pointed out that oscillatory orbits for shells in asymptotically flat spacetimes can be naturally obtained if the matter has a negative pressure component.

  2. Solution of the Roth-Marques-Durian Rotational Abrasion Model

    E-Print Network [OSTI]

    Bryan Gin-ge Chen

    2010-12-10T23:59:59.000Z

    We solve the rotational abrasion model of Roth, Marques and Durian (arXiv:1009.3492), a one-dimensional quasilinear partial differential equation resembling the inviscid Burgers equation with the unusual feature of a step function factor as a coefficient. The complexity of the solution is primarily in keeping track of the cases in the piecewise function that results from certain amputation and interpolation processes, so we also extract from it a model of an evolving planar tree graph that tracks the evolution of the coarse features of the contour.

  3. Toroidal L and H equilibria with axisymmetric rotations

    E-Print Network [OSTI]

    Tsui, K H

    2009-01-01T23:59:59.000Z

    Axisymmetric toroidal equilibria with toroidal and poloidal rotations are solved with a specific set of source functions. The two independent solutions are associated to L and H modes. The L/H transition is regarded as a bifurcation from one equilibrium configuration to another, under strong external heating and pellet injection to shape temperature and density profiles. Because of the steep edge gradient of the H solution, large static radial electric field, zonal flow, and improved confinements, come as consequences, not causes, of the H mode.

  4. Parity-odd effects and polarization rotation in graphene

    E-Print Network [OSTI]

    I. V. Fialkovsky; D. V. Vassilevich

    2009-02-15T23:59:59.000Z

    We show that the presence of parity-odd terms in the conductivity (or, in other words, in the polarization tensor of Dirac quasiparticles in graphene) leads to rotation of polarization of the electromagnetic waves passing through suspended samples of graphene. Parity-odd Chern-Simons type contributions appear in external magnetic field, giving rise to a quantum Faraday effect (though other sources of parity-odd effects may also be discussed). The estimated order of the effect is well above the sensitivity limits of modern optical instruments.

  5. Rotation-Enabled 7-DOF Seismometer | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin ofEnergy at Waste-to-Energy usingofRetrofittingFundA l i cRotation-Enabled 7-DOF

  6. Evolution of magnetized, differentially rotating neutron stars: Simulations in full general relativity

    E-Print Network [OSTI]

    Matthew D. Duez; Yuk Tung Liu; Stuart L. Shapiro; Masaru Shibata; Branson C. Stephens

    2006-05-12T23:59:59.000Z

    We study the effects of magnetic fields on the evolution of differentially rotating neutron stars, which can form in stellar core collapse or binary neutron star coalescence. Magnetic braking and the magnetorotational instability (MRI) both redistribute angular momentum; the outcome of the evolution depends on the star's mass and spin. Simulations are carried out in axisymmetry using our recently developed codes which integrate the coupled Einstein-Maxwell-MHD equations. For initial data, we consider three categories of differentially rotating, equilibrium configurations, which we label normal, hypermassive and ultraspinning. Hypermassive stars have rest masses exceeding the mass limit for uniform rotation. Ultraspinning stars are not hypermassive, but have angular momentum exceeding the maximum for uniform rotation at the same rest mass. We show that a normal star will evolve to a uniformly rotating equilibrium configuration. An ultraspinning star evolves to an equilibrium state consisting of a nearly uniformly rotating central core, surrounded by a differentially rotating torus with constant angular velocity along magnetic field lines, so that differential rotation ceases to wind the magnetic field. In addition, the final state is stable against the MRI, although it has differential rotation. For a hypermassive neutron star, the MHD-driven angular momentum transport leads to catastrophic collapse of the core. The resulting rotating black hole is surrounded by a hot, massive, magnetized torus undergoing quasistationary accretion, and a magnetic field collimated along the spin axis--a promising candidate for the central engine of a short gamma-ray burst. (Abridged)

  7. THE ROTATION PROFILE OF SOLAR MAGNETIC FIELDS BETWEEN {+-}60 Degree-Sign LATITUDES

    SciTech Connect (OSTI)

    Shi, X. J.; Xie, J. L., E-mail: shixiangjun@ynao.ac.cn [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

    2013-08-10T23:59:59.000Z

    Through a cross-correlation analysis of the Carrington synoptic maps of solar photospheric magnetic fields from Carrington Rotation Nos. 1625 to 2129 (from 1975 February to 2012 October), the sidereal rotation rates of solar magnetic fields between {+-}60 Degree-Sign latitudes are investigated. It seems that the temporal variation of rotation rates should be related to the solar cycle phase. The rotation profile of magnetic fields is obtained: the sidereal rotation rates decrease from the equator to mid-latitude and reach their minimum values of about 13.16 deg day{sup -1} (13.17 deg day{sup -1}) at 53 Degree-Sign (54 Degree-Sign ) latitude in the northern (southern) hemisphere, then increase toward higher latitudes. This rotation profile is different from the differential rotation law obtained by Snodgrass from a cross-correlation analysis of daily magnetograms, in which the rotation rates show a steep decrease from the equator to the poles. However, it is much closer to the quasi-rigid rotation law derived by Stenflo from an auto-correlation analysis of daily magnetograms. Some possible interpretations are discussed for the resulting rotation profile.

  8. Faraday Rotation Observations of Magnetic Fields in galaxy Clusters

    E-Print Network [OSTI]

    Tracy E. Clarke

    2004-12-10T23:59:59.000Z

    The presence of magnetic fields in the intracluster medium in clusters of galaxies has been revealed through several different observational techniques. These fields may be dynamically important in clusters as they will provide additional pressure support to the intracluster medium as well as inhibit transport mechanisms such as thermal conduction. Here, we review the current observational state of Faraday rotation measure studies of the cluster fields. The fields are generally found to be a few to 10 microG in non-cooling core clusters and ordered on scales of 10-20 kpc. Studies of sources at large impact parameters show that the magnetic fields extend from cluster cores to radii of at least 500 kpc. In central regions of cooling core systems the field strengths are often somewhat higher (10-40 microG) and appear to be ordered on smaller scales of a few to 10 kpc. We also review some of the recent work on interpreting Faraday rotation measure observations through theory and numerical simulations. These techniques allow us to build up a much more detailed view of the strength and topology of the fields.

  9. Parity-violating neutron spin rotation in hydrogen and deuterium

    E-Print Network [OSTI]

    Harald W. Griesshammer; Matthias R. Schindler; Roxanne P. Springer

    2012-01-23T23:59:59.000Z

    We calculate the (parity-violating) spin rotation angle of a polarized neutron beam through hydrogen and deuterium targets, using pionless effective field theory up to next-to-leading order. Our result is part of a program to obtain the five leading independent low-energy parameters that characterize hadronic parity-violation from few-body observables in one systematic and consistent framework. The two spin-rotation angles provide independent constraints on these parameters. Using naive dimensional analysis to estimate the typical size of the couplings, we expect the signal for standard target densities to be 10^-7 to 10^-6 rad/m for both hydrogen and deuterium targets. We find no indication that the nd observable is enhanced compared to the np one. All results are properly renormalized. An estimate of the numerical and systematic uncertainties of our calculations indicates excellent convergence. An appendix contains the relevant partial-wave projectors of the three-nucleon system.

  10. Physics of Intrinsic Rotation in Flux-Driven ITG Turbulence

    SciTech Connect (OSTI)

    Ku, S; Dimond, P H; Dif-Pradalier, G; Kwon, J M; Sarazin, Y; Hahm, T S; Garbet, X; Chang, C S; Latu, G; Yoon, E S; Ghendrih, Ph; Yi, S; Strugarek, A; Solomon, W

    2012-02-23T23:59:59.000Z

    Global, heat flux-driven ITG gyrokinetic simulations which manifest the formation of macroscopic, mean toroidal flow profiles with peak thermal Mach number 0.05, are reported. Both a particle-in-cell (XGC1p) and a semi-Lagrangian (GYSELA) approach are utilized without a priori assumptions of scale-separation between turbulence and mean fields. Flux-driven ITG simulations with different edge flow boundary conditions show in both approaches the development of net unidirectional intrinsic rotation in the co-current direction. Intrinsic torque is shown to scale approximately linearly with the inverse scale length of the ion temperature gradient. External momentum input is shown to effectively cancel the intrinsic rotation profile, thus confirming the existence of a local residual stress and intrinsic torque. Fluctuation intensity, intrinsic torque and mean flow are demonstrated to develop inwards from the boundary. The measured correlations between residual stress and two fluctuation spectrum symmetry breakers, namely E x B shear and intensity gradient, are similar. Avalanches of (positive) heat flux, which propagate either outwards or inwards, are correlated with avalanches of (negative) parallel momentum flux, so that outward transport of heat and inward transport of parallel momentum are correlated and mediated by avalanches. The probability distribution functions of the outward heat flux and the inward momentum flux show strong structural similarity

  11. Geothermal heating enhances atmospheric asymmetries on synchronously rotating planets

    E-Print Network [OSTI]

    Haqq-Misra, Jacob

    2014-01-01T23:59:59.000Z

    Earth-like planets within the liquid water habitable zone of M type stars may evolve into synchronous rotators. On these planets, the sub-stellar hemisphere experiences perpetual daylight while the opposing anti-stellar hemisphere experiences perpetual darkness. Because the night-side hemisphere has no direct source of energy, the air over this side of the planet is prone to freeze out and deposit on the surface, which could result in atmospheric collapse. However, general circulation models (GCMs) have shown that atmospheric dynamics can counteract this problem and provide sufficient energy transport to the anti-stellar side. Here we use an idealized GCM to consider the impact of geothermal heating on the habitability of synchronously rotating planets. Geothermal heating may be expected due to tidal interactions with the host star, and the effects of geothermal heating provide additional habitable surface area and may help to induce melting of ice on the anti-stellar hemisphere. We also explore the persisten...

  12. Thermo-Rotational Instability in Plasma Disks Around Compact Objects

    E-Print Network [OSTI]

    Bruno Coppi

    2008-02-12T23:59:59.000Z

    Differentially rotating plasma disks, around compact objects, that are imbedded in a ``seed'' magnetic field are shown to develop vertically localized ballooning modes that are driven by the combined radial gradient of the rotation frequency and vertical gradients of the plasma density and temperature. When the electron mean free path is shorter than the disk height and the relevant thermal conductivity can be neglected, the vertical particle flows produced by of these modes have the effect to drive the density and temperature profiles toward the ``adiabatic condition'' where $\\eta_{T}\\equiv(dlnT/dz)/(dlnn/dz)=2/3$. Here $T$ is the plasma temperature and $n$ the particle density. The faster growth rates correspond to steeper temperature profiles $(\\eta_{T}>2/3)$ such as those produced by an internal (e.g., viscous) heating process. In the end, ballooning modes excited for various values of $\\eta_{T}$ can lead to the evolution of the disk into a different current carrying configuration such as a sequence of plasma rings.

  13. Measurement of Gravitomagnetic and Acceleration Fields Around Rotating Superconductors

    E-Print Network [OSTI]

    M. Tajmar; F. Plesescu; B. Seifert; K. Marhold

    2006-10-17T23:59:59.000Z

    It is well known that a rotating superconductor produces a magnetic field proportional to its angular velocity. The authors conjectured earlier, that in addition to this so-called London moment, also a large gravitomagnetic field should appear to explain an apparent mass increase of Niobium Cooper-pairs. A similar field is predicted from Einstein's general relativity theory and the presently observed amount of dark energy in the universe. An experimental facility was designed and built to measure small acceleration fields as well as gravitomagnetic fields in the vicinity of a fast rotating and accelerating superconductor in order to detect this so-called gravitomagnetic London moment. This paper summarizes the efforts and results that have been obtained so far. Measurements with Niobium superconductors indeed show first signs which appear to be within a factor of 2 of our theoretical prediction. Possible error sources as well as the experimental difficulties are reviewed and discussed. If the gravitomagnetic London moment indeed exists, acceleration fields could be produced in a laboratory environment.

  14. Bulk emission of scalars by a rotating black hole

    E-Print Network [OSTI]

    M. Casals; S. R. Dolan; P. Kanti; E. Winstanley

    2008-07-17T23:59:59.000Z

    We study in detail the scalar-field Hawking radiation emitted into the bulk by a higher-dimensional, rotating black hole. We numerically compute the angular eigenvalues, and solve the radial equation of motion in order to find transmission factors. The latter are found to be enhanced by the angular momentum of the black hole, and to exhibit the well-known effect of superradiance. The corresponding power spectra for scalar fields show an enhancement with the number of dimensions, as in the non-rotating case. We compute the total mass loss rate of the black hole for a variety of black-hole angular momenta and bulk dimensions, and find that, in all cases, the bulk emission remains significantly smaller than the brane emission. The angular-momentum loss rate is also computed and found to have a smaller value in the bulk than on the brane. We present accurate bulk-to-brane emission ratios for a range of scenarios.

  15. On the Nuclear Rotation Curve of M31

    E-Print Network [OSTI]

    Thomas S. Statler

    1999-05-08T23:59:59.000Z

    The nuclear rotation curve of M31, as observed by the Hubble Space Telescope Faint Object Camera Spectrograph, shows a significant disturbance coinciding with the off-center brightness peak, P1. This +/- 60 km/s feature is distinguished by a local velocity maximum centered on P1 and a local minimum approxmately 0.08" closer to P2. If the M31 double nucleus is an eccentric disk with an off-center density concentration, as suggested by Tremaine, then the self-gravity of the disk can produce just such a disturbance. The expected kinematic signature is calculated approximately by examining sequences of closed periodic orbits in a Kepler potential perturbed by a model disk potential that precesses at constant frequency. The perturbation forces a steep negative eccentricity gradient in the sequence of closed orbits through the densest part of the disk, which reverses the arrangement of periapsis and apoapsis with respect to the central mass. Stars making up the inner part of the density concentration are at apoapsis, while stars making up the outer part are at periapsis, producing a steep local velocity gradient. This result is independent of the details of the mass distribution. The projected rotation curve of the model is shown to closely resemble that of M31, giving strong support to the eccentric disk picture.

  16. The rotating wind of the quasar PG 1700+518

    E-Print Network [OSTI]

    S. Young; D. J. Axon; A. Robinson; J. H. Hough; J. E. Smith

    2008-02-27T23:59:59.000Z

    It is now widely accepted that most galaxies undergo an active phase, during which a central super-massive black hole generates vast radiant luminosities through the gravitational accretion of gas. Winds launched from a rotating accretion disk surrounding the black hole are thought to play a critical role, allowing the disk to shed angular momentum that would otherwise inhibit accretion. Such winds are capable of depositing large amounts of mechanical energy in the host galaxy and its environs, profoundly affecting its formation and evolution, and perhaps regulating the formation of large-scale cosmological structures in the early Universe. Although there are good theoretical grounds for believing that outflows from active galactic nuclei originate as disk winds, observational verification has proven elusive. Here we show that structures observed in polarized light across the broad H-alpha emission line in the quasar PG 1700+158 originate close to the accretion disk in an electron scattering wind. The wind has large rotational motions (~4,000 km/s), providing direct observational evidence that outflows from active galactic nuclei are launched from the disks. Moreover, the wind rises nearly vertically from the disk, favouring launch mechanisms that impart an initial acceleration perpendicular to the disk plane.

  17. Berry's phase for a noncyclic rotation of light in a helically wound optical fiber

    SciTech Connect (OSTI)

    Morinaga, Atsuo; Monma, Akinori; Honda, Kazuhito; Kitano, Masao [Department of Physics, Faculty of Science and Technology, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan); Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyou-ku, Kyoto 615-8510 (Japan)

    2007-11-15T23:59:59.000Z

    We investigated Berry's phase for noncyclic evolution using the rotation of a polarization azimuth of linearly polarized light in a partially wound optical fiber over the surface of a cylinder. Using a rotation gauge around the rotation axis, the observed rotation of the polarization azimuth corresponds to the area of a spherical rectangle over the surface enclosed by the contour C of actual evolution, a large circle on the equator, and a longitudinal line connecting them, whereas the rotation of the polar gauge encloses a spherical triangle connecting the zenith of the sphere. The observed values were converted to Berry's phase by transformation from the rotation gauge to the geodesic gauge. Consequently, we could confirm that Berry's phase for a noncyclic evolution is given by the geodesic rule proposed by Samuel and Bhandari.

  18. Collapse of Magnetized Singular Isothermal Toroids: II. Rotation and Magnetic Braking

    E-Print Network [OSTI]

    Allen, A; Shu, F H

    2003-01-01T23:59:59.000Z

    We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic considerations, we idealize the pre-collapse core as a magnetized singular isothermal toroid, with a constant rotational speed everywhere. The collapse starts from the center, and propagates outwards in an inside-out fashion, satisfying exact self-similarity in space and time. For rotation rates and field strengths typical of dense low-mass cores, the main feature remains the flattening of the mass distribution along field lines -- the formation of a pseudodisk, as in the nonrotating cases. The density distribution of the pseudodisk is little affected by rotation. On the other hand, the rotation rate is strongly modified by pseudodisk formation. Most of the centrally accreted material reaches the vicinity of the protostar through the pseudodisk. The specific angular momentum can b...

  19. Effect of MLC leaf position, collimator rotation angle, and gantry rotation angle errors on intensity-modulated radiotherapy plans for nasopharyngeal carcinoma

    SciTech Connect (OSTI)

    Bai, Sen; Li, Guangjun; Wang, Maojie; Jiang, Qinfeng; Zhang, Yingjie [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China); Wei, Yuquan, E-mail: yuquawei@vip.sina.com [State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China)

    2013-07-01T23:59:59.000Z

    The purpose of this study was to investigate the effect of multileaf collimator (MLC) leaf position, collimator rotation angle, and accelerator gantry rotation angle errors on intensity-modulated radiotherapy plans for nasopharyngeal carcinoma. To compare dosimetric differences between the simulating plans and the clinical plans with evaluation parameters, 6 patients with nasopharyngeal carcinoma were selected for simulation of systematic and random MLC leaf position errors, collimator rotation angle errors, and accelerator gantry rotation angle errors. There was a high sensitivity to dose distribution for systematic MLC leaf position errors in response to field size. When the systematic MLC position errors were 0.5, 1, and 2 mm, respectively, the maximum values of the mean dose deviation, observed in parotid glands, were 4.63%, 8.69%, and 18.32%, respectively. The dosimetric effect was comparatively small for systematic MLC shift errors. For random MLC errors up to 2 mm and collimator and gantry rotation angle errors up to 0.5°, the dosimetric effect was negligible. We suggest that quality control be regularly conducted for MLC leaves, so as to ensure that systematic MLC leaf position errors are within 0.5 mm. Because the dosimetric effect of 0.5° collimator and gantry rotation angle errors is negligible, it can be concluded that setting a proper threshold for allowed errors of collimator and gantry rotation angle may increase treatment efficacy and reduce treatment time.

  20. Simulation of Alpha Particles in Rotating Plasma Interacting with a Stationary Ripple

    SciTech Connect (OSTI)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2011-01-11T23:59:59.000Z

    Superthermal ExB rotation can provide magnetohydrodynamic (MHD) stability and enhanced confinement to axisymmetric mirrors. However, the rotation speed has been limited by phenomena at end electrodes. A new prediction is that rotation might instead be produced using a magnetic ripple and alpha particle kinetic energy, in an extension of the alpha channeling concept. The interaction of alpha particles with the ripple results in visually interesting and practically useful orbits.

  1. Optical rotation in RbTiOAsO4 (point group mm2) W. Kaminsky*, I

    E-Print Network [OSTI]

    Kaminsky, Werner

    Optical rotation in RbTiOAsO4 (point group mm2) W. Kaminsky*, I , P. A. ThomasII and A. M. Glazer, UK Received March 5, 2001; accepted September 13, 2001 Abstract. Measurement of optical rotation in RbTiOAsO4 (RTA) with the tilter method resulted in an optical rotation of r12 ¼ þ17ð3Þ /mm

  2. Rotating charged hairy black hole in (2+1) dimensions and particle acceleration

    E-Print Network [OSTI]

    J. Sadeghi; B. Pourhassan; H. Farahani

    2013-10-26T23:59:59.000Z

    In this paper we construct rotating charged hairy black hole in (2+1) dimensions for infinitesimal black hole charge and rotation parameters. Then we consider this black hole as particle accelerator and calculate the center-of-mass energy of two colliding test particles near the rotating charged hairy black hole in (2+1) dimensions. As we expected, the center-of-mass energy has infinite value.

  3. Modification of the Doppler Effect due to the Helicity-Rotation Coupling

    E-Print Network [OSTI]

    Bahram Mashhoon

    2002-10-20T23:59:59.000Z

    The helicity-rotation coupling and its current empirical basis are examined. The modification of the Doppler effect due to the coupling of photon spin with the rotation of the observer is considered in detail in connection with its applications in the Doppler tracking of spacecraft. Further implications of this coupling and the possibility of searching for it in the intensity response of a rotating detector are briefly discussed.

  4. Doppler maps and surface differential rotation of EI Eri from the MUSICOS 1998 observations

    E-Print Network [OSTI]

    Zs. K?vári; A. Washuettl; B. H. Foing; K. Vida; J. Bartus; K. Oláh; the MUSICOS 98 team

    2008-11-03T23:59:59.000Z

    We present time-series Doppler images of the rapidly-rotating active binary star EI Eri from spectroscopic observations collected during the MUSICOS multi-site campaign in 1998, since the critical rotation period of 1.947 days makes it impossible to obtain time-resolved images from a single site. From the surface reconstructions a weak solar-type differential rotation, as well as a tiny poleward meridional flow are measured.

  5. Nonlinear mode coupling in rotating stars and the r-mode instability in neutron stars

    E-Print Network [OSTI]

    A. Katrin Schenk; Phil Arras; Eanna E. Flanagan; Saul A. Teukolsky; Ira Wasserman

    2001-07-11T23:59:59.000Z

    We develop the formalism required to study the nonlinear interaction of modes in rotating Newtonian stars in the weakly nonlinear regime. The formalism simplifies and extends previous treatments. At linear order, we elucidate and extend slightly a formalism due to Schutz, show how to decompose a general motion of a rotating star into a sum over modes, and obtain uncoupled equations of motion for the mode amplitudes under the influence of an external force. Nonlinear effects are added perturbatively via three-mode couplings. We describe a new, efficient way to compute the coupling coefficients, to zeroth order in the stellar rotation rate, using spin-weighted spherical harmonics. We apply this formalism to derive some properties of the coupling coefficients relevant to the nonlinear interactions of unstable r-modes in neutron stars, postponing numerical integrations of the coupled equations of motion to a later paper. From an astrophysical viewpoint, the most interesting result of this paper is that many couplings of r-modes to other rotational modes (modes with zero frequencies in the non-rotating limit) are small: either they vanish altogether because of various selection rules, or they vanish to lowest order in the angular velocity. In zero-buoyancy stars, the coupling of three r-modes is forbidden entirely and the coupling of two r-modes to one hybrid rotational mode vanishes to zeroth order in rotation frequency. In incompressible stars, the coupling of any three rotational modes vanishes to zeroth order in rotation frequency.

  6. A Performance Comparison of Condition Based Monitoring Damage Features Used in Rotating Machines under Variable Conditions /

    E-Print Network [OSTI]

    Robinson, Luke Thomas

    2013-01-01T23:59:59.000Z

    detection for structural health monitoring using Holderplacement for structural health monitoring with applicationRotating Machinery, Structural Health Monitoring, Shock and

  7. Low-Cost Alternative External Rotation Shoulder Brace and Review of Treatment in Acute Shoulder Dislocations

    E-Print Network [OSTI]

    Lacy, Kyle; Cooke, Chris; Cooke, Pat; Schupbach, Justin; Vaidya, Rahul

    2015-01-01T23:59:59.000Z

    Amazon.com Corflex® Shoulder Abduction Pillow Sling Corflex® ER Shoulder Abduction Pillow with Sling Maxar® AS-300™shoulder in a position of abduction and external rotation.

  8. Webinar: Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique

    Broader source: Energy.gov [DOE]

    Video recording of the Fuel Cell Technologies Office webinar, Testing Oxygen Reduction Reaction Activity with the Rotating Disc Electrode Technique, originally presented on March 12, 2013.

  9. Null Result for the Violation of Equivalence Principle with Free-Fall Rotating Gyroscopes

    E-Print Network [OSTI]

    Luo, J; Zhang, Y Z; Zhou, Z B

    2002-01-01T23:59:59.000Z

    The differential acceleration between a rotating mechanical gyroscope and a non-rotating one is directly measured by using a double free-fall interferometer, and no apparent differential acceleration has been observed at the relative level of 2x10{-6}. It means that the equivalence principle is still valid for rotating extended bodies, i.e., the spin-gravity interaction between the extended bodies has not been observed at this level. Also, to the limit of our experimental sensitivity, there is no observed asymmetrical effect or anti-gravity of the rotating gyroscopes as reported by hayasaka et al.

  10. arthroscopic double-row rotator: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rotational theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when...

  11. asphalt-rubber rotational viscosity: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at birth. A fraction of the gravitational binding energy of collapse is stored in the free energy of differential rotation. This energy source may be tapped by viscous...

  12. Primary, secondary instabilities and control of the rotating-disk boundary layer

    E-Print Network [OSTI]

    ;Typical 3D boundary layers rotating disk swept wing Common features: · crossflow component near the wall · inflection point · strong inviscid instability · secondary instabilities ; growth and saturation of crossflow

  13. Modeling Poplar Growth as a Short Rotation Woody Crop for Biofuels

    E-Print Network [OSTI]

    Hart, Quinn James

    2014-01-01T23:59:59.000Z

    a Short Rotation Woody Crop for Biofuels Q. J. Hart 1,? , O.for cellulosic derived biofuels. The ability to accuratelycrops for bioenergy and biofuels applications. In vitro

  14. Dark matter transport properties and rapidly rotating neutron stars

    E-Print Network [OSTI]

    C. J. Horowitz

    2012-05-16T23:59:59.000Z

    Neutron stars are attractive places to look for dark matter because their high densities allow repeated interactions. Weakly interacting massive particles (WIMPs) may scatter efficiently in the core or in the crust of a neutron star. In this paper we focus on WIMP contributions to transport properties, such as shear viscosity or thermal conductivity, because these can be greatly enhanced by long mean free paths. We speculate that WIMPs increase the shear viscosity of neutron star matter and help stabilize r-mode oscillations. These are collective oscillations where the restoring force is the Coriolis force. At present r-modes are thought to be unstable in many observed rapidly rotating stars. If WIMPs stabilize the r-modes, this would allow neutron stars to spin rapidly. This likely requires WIMP-nucleon cross sections near present experimental limits and an appropriate density of WIMPs in neutron stars.

  15. Periodic relativity: deflection of light, acceleration, rotation curves

    E-Print Network [OSTI]

    Vikram H. Zaveri

    2014-12-08T23:59:59.000Z

    Vectorial analysis relating to derivation of deflection of light is presented. Curvilinear acceleration is distinguished from the Newtonian polar conic acceleration. The difference between the two is due to the curvature term. Lorentz invariant expression for acceleration is derived. A physical theory of rotation curves of galaxies based on second solution to Einstein's field equation is presented. Theory is applied to Milky Way, M31, NGC3198 and Solar system. Modified Kepler's third law yields correct orbital periods of stars in a galaxy. Deviation factor in the line element of the theory happens to be the ratio of the Newtonian gravitational acceleration to the measured acceleration of the star in the galaxy. Therefore this deviation factor can replace the MOND function.

  16. Exact Rotating Magnetic Traversable Wormholes satisfying the Energy Conditions

    E-Print Network [OSTI]

    Matos, Tonatiuh

    2015-01-01T23:59:59.000Z

    In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field) with an arbitrary coupling constant, as source of gravitation. We obtain an exact solution of the Einstein equations using this source that represents a magnetized rotating WH. This space-time has a naked ring singularity, probably untouchable as in \\cite{Matos:2012gj}, but otherwise regular. The WH throat lies on the disc bounded by the ring singularity, which keeps the throat open without requiring exotic matter, that means, satisfying all the energy conditions. After analyzing the geodesic motion and the tidal forces we find that a test particle can go through the WH without troubles.

  17. Quantum metrology with rotating matter waves in different geometries

    SciTech Connect (OSTI)

    Dunningham, J. A.; Cooper, J. J.; Hallwood, D. W. [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Institute of Natural Sciences, Massey University, Private Bag 102904, Auckland (New Zealand)

    2012-09-01T23:59:59.000Z

    A promising practical application of entanglement is metrology, where quantum states can be used to make measurements beyond the shot noise limit. Here we consider how metrology schemes could be realised using atomic Bose-Einstein condensates (BECs) trapped in different potentials. In particular, we show that if a trapped BEC is rotated at just the right frequency, it can undergo a quantum phase transition characterised by large-scale entanglement spreading across the system. This simple process of stirring can generate interesting quantum states such as macroscopic superpositions of all the atoms flowing in opposite directions around a ring-shaped potential. We consider different trapping potentials and show how this leads to different entangled states. In particular, we find that by reducing the dimensionality of the system to one or two dimensions, it is possible to generate entangled states that are remarkably robust to the loss of atoms and so are ideally suited to precision measurement schemes.

  18. Innovative Sensors for Pipeline Crawlers: Rotating Permanent Magnet Inspection

    SciTech Connect (OSTI)

    J. Bruce Nestleroth; Richard J. Davis; Stephanie Flamberg

    2006-09-30T23:59:59.000Z

    Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they may encounter. To facilitate inspection of these ''unpiggable'' pipelines, recent inspection development efforts have focused on a new generation of powered inspection platforms that are able to crawl slowly inside a pipeline and can maneuver past the physical barriers that limit internal inspection applicability, such as bore restrictions, low product flow rate, and low pressure. The first step in this research was to review existing inspection technologies for applicability and compatibility with crawler systems. Most existing inspection technologies, including magnetic flux leakage and ultrasonic methods, had significant implementation limitations including mass, physical size, inspection energy coupling requirements and technology maturity. The remote field technique was the most promising but power consumption was high and anomaly signals were low requiring sensitive detectors and electronics. After reviewing each inspection technology, it was decided to investigate the potential for a new inspection method. The new inspection method takes advantage of advances in permanent magnet strength, along with their wide availability and low cost. Called rotating permanent magnet inspection (RPMI), this patent pending technology employs pairs of permanent magnets rotating around the central axis of a cylinder to induce high current densities in the material under inspection. Anomalies and wall thickness variations are detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. This inspection method is an alternative to the common concentric coil remote field technique that induces low-frequency eddy currents in ferromagnetic pipes and tubes. Since this is a new inspection method, both theory and experiment were used to determine fundamental capabilities and limitations. Fundamental finite element modeling analysis and experimental investigations performed during this development have led to the derivation of a first order analytical equation for designing rotating magnetizers to induce current and positioning sensors to record signals from anomalies. Experimental results confirm the analytical equation and the finite element calculations provide a firm basis for the design of RPMI systems. Experimental results have shown that metal loss anomalies and wall thickness variations can be detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. The design exploits the phenomenon that circumferential currents are easily detectable at distances well away from the magnets. Current changes at anomalies were detectable with commercial low cost Hall Effect sensors. Commercial analog to digital converters can be used to measure the sensor output and data analysis can be performed in real time using PC computer systems. The technology was successfully demonstrated during two blind benchmark tests where numerous metal loss defects were detected. For this inspection technology, the detection threshold is a function of wall thickness and corrosion depth. For thinner materials, the detection threshold was experimentally shown to be comparable to magnetic flux leakage. For wall thicknesses greater than three tenths of an inch, the detection threshold increases with wall thickness. The potential for metal loss anomaly sizing was demonstrated in the second benchmarking study, again with accuracy comparable to existing magnetic flux leakage technologies. The rotating permanent magnet system has the potential for inspecting unpiggable pipelines since the magnetizer configurations can be sufficiently small with respect to the bore of the pipe to pass obstructions that limit the application of many i

  19. Turbulent Transport in Tokamak Plasmas with Rotational Shear

    SciTech Connect (OSTI)

    Barnes, M.; Highcock, E. G. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP (United Kingdom); Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Parra, F. I.; Schekochihin, A. A. [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3NP (United Kingdom); Cowley, S. C.; Roach, C. M. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

    2011-04-29T23:59:59.000Z

    Nonlinear gyrokinetic simulations are conducted to investigate turbulent transport in tokamak plasmas with rotational shear. At sufficiently large flow shears, linear instabilities are suppressed, but transiently growing modes drive subcritical turbulence whose amplitude increases with flow shear. This leads to a local minimum in the heat flux, indicating an optimal ExB shear value for plasma confinement. Local maxima in the momentum fluxes are observed, implying the possibility of bifurcations in the ExB shear. The critical temperature gradient for the onset of turbulence increases with flow shear at low flow shears; at higher flow shears, the dependence of heat flux on temperature gradient becomes less stiff. The turbulent Prandtl number is found to be largely independent of temperature and flow gradients, with a value close to unity.

  20. Nanoparticles at liquid interfaces: Rotational dynamics and angular locking

    SciTech Connect (OSTI)

    Razavi, Sepideh; Kretzschmar, Ilona [Department of Chemical Engineering, City College of City University of New York, New York, New York 10031 (United States)] [Department of Chemical Engineering, City College of City University of New York, New York, New York 10031 (United States); Koplik, Joel [Department of Physics and The Benjamin Levich Institute for Physico-chemical Hydrodynamics, City College of City University of New York, New York, New York 10031 (United States)] [Department of Physics and The Benjamin Levich Institute for Physico-chemical Hydrodynamics, City College of City University of New York, New York, New York 10031 (United States); Colosqui, Carlos E., E-mail: carlos.colosqui@stonybrook.edu [Department of Mechanical Engineering, Stony Brook University, Stony Brook, New York 11794 (United States)

    2014-01-07T23:59:59.000Z

    Nanoparticles with different surface morphologies that straddle the interface between two immiscible liquids are studied via molecular dynamics simulations. The methodology employed allows us to compute the interfacial free energy at different angular orientations of the nanoparticle. Due to their atomistic nature, the studied nanoparticles present both microscale and macroscale geometrical features and cannot be accurately modeled as a perfectly smooth body (e.g., spheres and cylinders). Under certain physical conditions, microscale features can produce free energy barriers that are much larger than the thermal energy of the surrounding media. The presence of these energy barriers can effectively “lock” the particle at specific angular orientations with respect to the liquid-liquid interface. This work provides new insights on the rotational dynamics of Brownian particles at liquid interfaces and suggests possible strategies to exploit the effects of microscale features with given geometric characteristics.

  1. Arbitrary Rotation Invariant Random Matrix Ensembles and Supersymmetry

    E-Print Network [OSTI]

    Thomas Guhr

    2006-06-03T23:59:59.000Z

    We generalize the supersymmetry method in Random Matrix Theory to arbitrary rotation invariant ensembles. Our exact approach further extends a previous contribution in which we constructed a supersymmetric representation for the class of norm-dependent Random Matrix Ensembles. Here, we derive a supersymmetric formulation under very general circumstances. A projector is identified that provides the mapping of the probability density from ordinary to superspace. Furthermore, it is demonstrated that setting up the theory in Fourier superspace has considerable advantages. General and exact expressions for the correlation functions are given. We also show how the use of hyperbolic symmetry can be circumvented in the present context in which the non-linear sigma model is not used. We construct exact supersymmetric integral representations of the correlation functions for arbitrary positions of the imaginary increments in the Green functions.

  2. Rotating Hayward's regular black hole as particle accelerator

    E-Print Network [OSTI]

    Muhammed Amir; Sushant G. Ghosh

    2015-06-10T23:59:59.000Z

    Recently, Ban\\~{a}dos, Silk and West (BSW) demonstrated that the extremal Kerr black hole can act as a particle accelerator with arbitrarily high center-of-mass energy ($E_{CM}$) when the collision takes place near the horizon. The rotating Hayward's regular black hole, apart from Mass ($M$) and angular momentum ($a$), has a new parameter $g$ ($g>0$ is a constant) that provides a deviation from the Kerr black hole. We demonstrate that for each $g$, with $M=1$, there exist critical $a_{E}$ and $r_{H}^{E}$, which corresponds to a regular extremal black hole with degenerate horizon, and $a_{E}$ decreases and $r_{H}^{E}$ increases with increase in $g$. While $aparticle accelerator and thus in turn may provide a suitable framework for Plank-scale physics. For a non-extremal case, there always exist a finite upper bound of $E_{CM}$, which increases with deviation parameter $g$.

  3. Testing the isotropy of space using rotating quartz oscillators

    E-Print Network [OSTI]

    Anthony Lo; Philipp Haslinger; Eli Mizrachi; Loic Anderegg; Holger Müller; Michael Hohensee; Maxim Goryachev; Michael E Tobar

    2015-01-28T23:59:59.000Z

    Violations of Lorentz invariance by matter and light can generate direction- and frame-dependent anisotropies in particles inertial masses and, hence, a measurable modulation of the oscillation frequency of rotating quartz crystal oscillators. This allows simple and low maintenance experiments that are ideally suited for long-term data taking. Using the Standard Model Extension (SME) as a parameterizing framework, we study the magnitude of this putative frequency modulation. A preliminary experiment with room-temperature SC-cut crystals yields a frequency resolution in the $10^{-15}$ range with $\\sim 120$ hours of data and a limit of $\\tilde c_Q=(-1.8 \\pm 2.2)\\times 10^{-14}$\\,GeV on the most weakly constrained neutron-sector $c-$coefficient of the SME. Future experiments with cryogenic oscillators promise additional improvements in accuracy, opening up the potential for improved tests of Lorentz symmetry in the neutron, proton, electron and photon sector.

  4. Novel Carbon Films for Next Generation Rotating Equipment Applications

    SciTech Connect (OSTI)

    Michael McNallan; Ali Erdemir; Yury Gogotsi

    2006-02-20T23:59:59.000Z

    This report describes the results of research performed on a new generation of low friction, wear resistant carbon coatings for seals and bearings in high speed rotating equipment. The low friction coatings, Near Frictionless Carbon (NFC), a high hydrogen content diamondlike carbon, and Carbide Derived Carbon (CDC), a conversion coating produced on the surfaces of metal carbides by halogenation, can be applied together or separately to improve the performance of seals and bearings, with benefits to energy efficiency and environmental protection. Because hard carbide ceramics, such as silicon carbide, are widely used in the seals industry, this coating is particularly attractive as a low cost method to improve performance. The technology of CDC has been licensed to an Illinois company, Carbide Derivative Technologies, Inc. (CDTI) to implement the commercialization of this material.

  5. Rotation Rate of Particle Pairs in Homogeneous Isotropic Turbulence

    E-Print Network [OSTI]

    Daddi-Moussa-Ider, Abdallah

    2015-01-01T23:59:59.000Z

    Understanding the dynamics of particles in turbulent flow is important in many environmental and industrial applications. In this paper, the statistics of particle pair orientation is numerically studied in homogeneous isotropic turbulent flow, with Taylor microscale Rynolds number of 300. It is shown that the Kolmogorov scaling fails to predict the observed probability density functions (PDFs) of the pair rotation rate and the higher order moments accurately. Therefore, a multifractal formalism is derived in order to include the intermittent behavior that is neglected in the Kolmogorov picture. The PDFs of finding the pairs at a given angular velocity for small relative separations, reveals extreme events with stretched tails and high kurtosis values. Additionally, The PDFs are found to be less intermittent and follow a complementary error function distribution for larger separations.

  6. A Rotating Electrode System for the Generation of Metal Alloy Microspheres 

    E-Print Network [OSTI]

    Thompson, Chad 1984-

    2012-11-28T23:59:59.000Z

    powder feed for fabrication. A simple and economic option for laboratory scale powder production is the Rotating Electrode Process (REP), which produces microsphere shaped powder by melting the tip of a rotating bar with an electric arc. In order to fully...

  7. Rotational stabilization of pinch instabilities in Taylor-Couette flow Dima Shalybkov*

    E-Print Network [OSTI]

    Rotational stabilization of pinch instabilities in Taylor-Couette flow Dima Shalybkov* A.F. Ioffe Institute for Physics and Technology, 194021, St. Petersburg, Russia Received 25 October 2006; published 11-known pinch type instability. The stable rotation stabilizes the unstable azimuthal magnetic field

  8. Faraday rotation enhancement of gold coated Fe2O3 nanoparticles: comparison of experiment and theory

    E-Print Network [OSTI]

    Wysin, Gary

    Faraday rotation enhancement of gold coated Fe2O3 nanoparticles: comparison of experiment to evaluate their potential for application. In this study, the Faraday rotation enhancement of gold coated Fe2O3 nanoparticles (NP) is investigated experimentally and theoretically. The experiment shows

  9. Rotation Angle for the Optimum Tracking of One-Axis Trackers

    SciTech Connect (OSTI)

    Marion, W. F.; Dobos, A. P.

    2013-07-01T23:59:59.000Z

    An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

  10. Thermoelectric Rotating Torus for Fusion A. B. Hassam and Yi-Min Huang

    E-Print Network [OSTI]

    Hassam, Adil

    Thermoelectric Rotating Torus for Fusion A. B. Hassam and Yi-Min Huang Institute for Plasma power maintains the rotation and also heats the plasma. The thermoelectric effect from the resultingRevLett.91.195002 PACS numbers: 52.58.­c, 52.30.­q, 52.55.­s In magnetized plasma, thermoelectric currents

  11. Multipole-multimode Floquet theory of rotational resonance width experiments: 13

    E-Print Network [OSTI]

    Griffin, Robert G.

    Multipole-multimode Floquet theory of rotational resonance width experiments: 13 C­13 C distance description of zero-quantum ZQ NMR processes using multipole-multimode Floquet theory is proposed for studying in rotational resonance width R2 W ex- periments based on multipole-multimode Floquet theory MMFT . The approach

  12. Generalized Quaternion and Rotation in 3-space E (3-alfa,beta)

    E-Print Network [OSTI]

    Mehdi Jafari; Yusuf Yayli

    2015-02-01T23:59:59.000Z

    The paper explains how a unit generalized quaternion is used to represent a rotation of a vector in 3-dimensional space. We review of some algebraic properties of generalized quaternions and operations between them and then show their relation with the rotation matrix.

  13. WAVE-DRIVEN ROTATION IN CENTRIFUGAL MIRRORS Abraham J. Fetterman and Nathaniel J. Fisch

    E-Print Network [OSTI]

    by harnessing alpha particle energy. This is an exten- sion of the alpha channeling effect. The alpha particleWAVE-DRIVEN ROTATION IN CENTRIFUGAL MIRRORS Abraham J. Fetterman and Nathaniel J. Fisch Department frequency waves. A fixed azimuthal ripple is a simple and efficient wave that could produce rotation

  14. Acoustic oscillations in rapidly rotating polytropic stars I. Effects of the centrifugal distortion

    E-Print Network [OSTI]

    F. Lignieres; M. Rieutord; D. Reese

    2006-04-13T23:59:59.000Z

    A new non-perturbative method to compute accurate oscillation modes in rapidly rotating stars is presented. In this paper, the effect of the centrifugal force is fully taken into account while the Coriolis force is neglected. This assumption is valid when the time scale of the oscillation is much shorter than the inverse of the rotation rate and is expected to be suitable for high radial order p-modes of $\\delta$ Scuti stars. Axisymmetric p-modes have been computed in uniformly rotating polytropic models of stars. In the frequency and rotation range considered, we found that as rotation increases (i) the asymptotic structure of the non-rotating frequency spectrum is first destroyed then replaced by a new form of organization (ii) the mode amplitude tends to concentrate near the equator (iii) differences with perturbative methods become significant as soon as the rotation rate exceeds about fifteen percent of the Keplerian limit. The implications for the seismology of rapidly rotating stars are then discussed.

  15. The effect of diamagnetic flows on turbulent driven ion toroidal rotation

    SciTech Connect (OSTI)

    Lee, J. P. [Courant Institute of Mathematical Sciences, New York University, New York, New York 10003 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10003 (United States); Barnes, M. [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)] [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States); Parra, F. I. [Rudolf Peierls Centre for Theoretical Physics, Oxford University, Oxford OX1 3NP (United Kingdom)] [Rudolf Peierls Centre for Theoretical Physics, Oxford University, Oxford OX1 3NP (United Kingdom); Belli, E. A.; Candy, J. [General Atomics, San Diego, California 92121 (United States)] [General Atomics, San Diego, California 92121 (United States)

    2014-05-15T23:59:59.000Z

    Turbulent momentum redistribution determines the radial profile of rotation in a tokamak. The momentum transport driven by diamagnetic flow effects is an important piece of the radial momentum transport for sub-sonic rotation, which is often observed in experiments. In a non-rotating state, the diamagnetic flow and the E × B flow must cancel. The diamagnetic flow and the E × B flow have different effects on the turbulent momentum flux, and this difference in behavior induces intrinsic rotation. The momentum flux is evaluated using gyrokinetic equations that are corrected to higher order in the ratio of the poloidal Larmor radius to the minor radius, which requires evaluation of the diamagnetic corrections to Maxwellian equilibria. To study the momentum transport due to diamagnetic flow effects, three experimental observations of ion rotation are examined. First, a strong pressure gradient at the plasma edge is shown to result in a significant inward momentum transport due to the diamagnetic effect, which may explain the observed peaking of rotation in a high confinement mode. Second, the direction of momentum transport is shown to change as collisionality increases, which is qualitatively consistent with the observed reversal of intrinsic rotation by varying plasma density and current. Last, the dependence of the intrinsic momentum flux on the magnetic shear is found, and it may explain the observed rotation changes in the presence of lower hybrid current drive.

  16. A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers

    E-Print Network [OSTI]

    Fournier, Alexandre

    A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers Abstract We present a Fourier-spectral element approach for modeling thermal convection in a rotating, Spectral Methods for Axisymmetric Domains, Gauthier-Villars, Paris, 1999], a Fourier expansion of the field

  17. AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling

    E-Print Network [OSTI]

    McCaffrey, Robert

    AGU Monograph, Plate Boundary Zones, in press. Page 1 Crustal Block Rotations and Plate Coupling that considering both block rotations and fault locking significantly improves the fit to the data over models by locking on #12;AGU Monograph, Plate Boundary Zones, in press. Page 2 block-bounding faults and apply

  18. Single-ended counter-rotating radial turbine for space application

    DOE Patents [OSTI]

    Coomes, E.P.; Wilson, D.G.; Webb, B.J.; McCabe, S.J.

    1987-05-13T23:59:59.000Z

    A single-ended turbine with counter-rotating blades operating with sodium as the working fluid. The single-ended, counter-rotating feature of the turbine results in zero torque application to a space platform. Thus, maneuvering of the platform is not adversely affected by the turbine. 4 figs.

  19. The Rotational Propulsion Characteristics of Scaled-up Helical Microswimmers with different heads and magnetic positioning

    E-Print Network [OSTI]

    of the cut-off frequency. The rotational propulsion characteristics of helical swimmers with a magnetic headThe Rotational Propulsion Characteristics of Scaled-up Helical Microswimmers with different heads and magnetic positioning Tiantian Xu1, Gilgueng Hwang2, Nicolas Andreff3 and St´ephane R´egnier1 Abstract

  20. Parametric mechanism of the rotation energy pumping by a relativistic plasma

    E-Print Network [OSTI]

    G. Z. Machabeli; Zaza Osmanov; Swadesh M. Mahajan

    2006-09-14T23:59:59.000Z

    An investigation of the kinematics of a plasma stream rotating in the pulsar magnetosphere is presented. On the basis of an exact set of equations describing the behavior of the plasma stream, the increment of the instability is obtained, and the possible relevance of this approach for the understanding of the pulsar rotation energy pumping mechanism is discussed.

  1. American Institute of Aeronautics and Astronautics An Experimental Investigation on the Effects of Turbine Rotation

    E-Print Network [OSTI]

    Hu, Hui

    of Turbine Rotation Directions on the Wake Interference of Wind Turbines Wei Yuan1 , Ahmet Ozbay2 , Wei Tian3 to investigate on the effects of the relative rotation directions of two tandwm wind turbines on the power production performance and flow characteristics in the wakes of two wind turbines in tandem. The experimental

  2. Rotational energy analysis for rotatingvibrating linear molecules in classical trajectory simulation

    E-Print Network [OSTI]

    Kim, Myung Soo

    Rotational energy analysis for rotating­vibrating linear molecules in classical trajectory-specific vibrational energy analysis reported previously, the present method allows a reliable separation of the total calculation,6 one wishes to carry out mode-specific energy analysis at the end of each trajectory run

  3. ccsd-00021948,version1-29Mar2006 Bose-Einstein condensates in fast rotation

    E-Print Network [OSTI]

    Boyer, Edmond

    ccsd-00021948,version1-29Mar2006 Bose-Einstein condensates in fast rotation S. Stock, B. Battelier of atomic Bose-Einstein condensates confined in quadratic or quartic potentials, and give an overview the physics of condensates containing a single vortex line. We then address the regime of fast rotation

  4. ccsd00003161, Vortex patterns in a fast rotating Bose-Einstein condensate

    E-Print Network [OSTI]

    . Furthermore we restrict our analysis to the case of a two-dimensional gas in the xy plane, assumingccsd­00003161, version 1 ­ 26 Oct 2004 Vortex patterns in a fast rotating Bose-Einstein condensate, France (Dated: October 26, 2004) For a fast rotating condensate in a harmonic trap, we investigate

  5. Elliptical-inertial instability of rotating Karman vortex streets A. Stegnera

    E-Print Network [OSTI]

    Stegner Alexandre

    Elliptical-inertial instability of rotating Karman vortex streets A. Stegnera Laboratoire de. Unlike the classical bidimensional Karman street, these observed vortex streets are affected by the earth Karman streets. A series of experiments were performed to study the wake of a cylinder in a rotating deep

  6. Establishment phase greenhouse gas emissions in short rotation woody biomass plantations

    E-Print Network [OSTI]

    Turner, Monica G.

    to short-rotation woody biomass crops (SRWC) for bioenergy in the Northern U.S. Lake States. GHG debts-rotation woody bio- energy crops (SRWC), specifically hybrid-poplar (Populus spp.) and willow (Salix spp.), being in the Northern Lake States, USA Marin M. Palmer a, *, Jodi A. Forrester a , David E. Rothstein b , David J

  7. Sub-Kelvin refrigeration with dry-coolers on a rotating system

    E-Print Network [OSTI]

    Oguri, S; Choi, J; Kawai, M; Tajima, O

    2014-01-01T23:59:59.000Z

    We developed a cryogenic system on a rotating table that achieves sub-Kelvin conditions. The cryogenic system consists of a helium sorption cooler and a pulse tube cooler in a cryostat mounted on a rotating table. Two rotary-joint connectors for electricity and helium gas circulation enable the coolers to be operated and maintained with ease. We performed cool-down tests under a condition of continuous rotation at 20 rpm. We obtained a temperature of 0.23 K with a holding time of more than 24 hours, thus complying with catalog specifications. We monitored the system's performance for four weeks; two weeks with and without rotation. A few-percent difference in conditions was observed between these two states. Most applications can tolerate such a slight difference. The technology developed is useful for various scientific applications requiring sub-Kelvin conditions on rotating platforms.

  8. Rotation numbers of invariant manifolds around unstable periodic orbits for the diamagnetic Kepler problem

    E-Print Network [OSTI]

    Zuo-Bing Wu

    2008-03-17T23:59:59.000Z

    In this paper, a method to construct topological template in terms of symbolic dynamics for the diamagnetic Kepler problem is proposed. To confirm the topological template, rotation numbers of invariant manifolds around unstable periodic orbits in a phase space are taken as an object of comparison. The rotation numbers are determined from the definition and connected with symbolic sequences encoding the periodic orbits in a reduced Poincar\\'e section. Only symbolic codes with inverse ordering in the forward mapping can contribute to the rotation of invariant manifolds around the periodic orbits. By using symbolic ordering, the reduced Poincar\\'e section is constricted along stable manifolds and a topological template, which preserves the ordering of forward sequences and can be used to extract the rotation numbers, is established. The rotation numbers computed from the topological template are the same as those computed from their original definition.

  9. The radiative heat transfer between a rotating nanoparticle and a plane surface

    E-Print Network [OSTI]

    Vahid Ameri; Mehdi Shafei Aporvari; Fardin Kheirandish

    2015-06-03T23:59:59.000Z

    Based on a microscopic approach, we propose a Lagrangian for the combined system of a rotating dielectric nanoparticle above a plane surface in the presence of electromagnetic vacuum fluctuations. In the framework of canonical quantization, the electromagnetic vacuum field is quantized in the presence of dielectric fields describing the nanoparticle and a semi-infinite dielectric with planar interface. The radiative heat power absorbed by the rotating nanoparticle is obtained and the result is in agreement with previous results when the the rotational frequency of the nanoparticle is zero or much smaller than the relaxation frequency of the dielectrics. The well known near field effect is reexamined and discussed in terms of the rotational frequency. The radiative heat power absorbed by the nanoparticle for well-known peak frequencies, is plotted in terms of the rotational frequency showing an interesting effect resembling a phase transition around a critical frequency, determined by the relaxation frequency of the dielectrics.

  10. Non-commutative Quantum Mechanics in Three Dimensions and Rotational Symmetry

    E-Print Network [OSTI]

    Debabrata Sinha; Biswajit Chakraborty; Frederik G Scholtz

    2011-08-12T23:59:59.000Z

    We generalize the formulation of non-commutative quantum mechanics to three dimensional non-commutative space. Particular attention is paid to the identification of the quantum Hilbert space in which the physical states of the system are to be represented, the construction of the representation of the rotation group on this space, the deformation of the Leibnitz rule accompanying this representation and the implied necessity of deforming the co-product to restore the rotation symmetry automorphism. This also implies the breaking of rotational invariance on the level of the Schroedinger action and equation as well as the Hamiltonian, even for rotational invariant potentials. For rotational invariant potentials the symmetry breaking results purely from the deformation in the sense that the commutator of the Hamiltonian and angular momentum is proportional to the deformation.

  11. Limited spatial region for synchronous beam-wave interactions in rotating mode resonators

    SciTech Connect (OSTI)

    Velazco, J.E. (Microwave Research Laboratory, Department of Electric and Computer Engineering, George Mason University, Fairfax, Virginia 22030 (United States)); Mako, F.M. (FM Technologies, Inc., Fairfax, Virginia 22032 (United States))

    1993-11-29T23:59:59.000Z

    An electron beam passing along an axisymmetric static magnetic field under the presence of circularly polarized electromagnetic fields, launched in a suitable rotating mode resonator, can propagate as a growing helix. This helix rotates temporally with an angular velocity equal to that of the cavity's rotating mode. When the axial magnetic field is adjusted to obtain matching between the electrons gyrofrequency and fields rotating frequency, the electrons maintain phase coherence with the wave during the interaction. Synchronous beam-wave interactions will be shown to be limited to a spatial region near the resonator axis. This limited synchronous region results from the rotating-wave phase velocity exceeding the velocity of the particle beam.

  12. BONA FIDE, STRONG-VARIABLE GALACTIC LUMINOUS BLUE VARIABLE STARS ARE FAST ROTATORS: DETECTION OF A HIGH ROTATIONAL VELOCITY IN HR CARINAE

    SciTech Connect (OSTI)

    Groh, J. H. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Damineli, A.; Moises, A. P.; Teodoro, M. [Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Rua do Matao 1226, Cidade Universitaria, 05508-090, Sao Paulo, SP (Brazil); Hillier, D. J. [Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, PA 15260 (United States); Barba, R. [Departamento de fisica, Universidad de La Serena, Benavente 980, La Serena (Chile); Fernandez-Lajus, E.; Gamen, R. C.; Solivella, G., E-mail: jgroh@mpifr-bonn.mpg.d [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, and Instituto de Astrofisica de La Plata (CCT La Plata-CONICET), Paseo del Bosque S/N, B1900FWA, La Plata (Argentina)

    2009-11-01T23:59:59.000Z

    We report optical observations of the luminous blue variable (LBV) HR Carinae which show that the star has reached a visual minimum phase in 2009. More importantly, we detected absorptions due to Si IV lambdalambda4088-4116. To match their observed line profiles from 2009 May, a high rotational velocity of v{sub rot} approx = 150 +- 20 km s{sup -1} is needed (assuming an inclination angle of 30 deg.), implying that HR Car rotates at approx =0.88 +- 0.2 of its critical velocity for breakup (v{sub crit}). Our results suggest that fast rotation is typical in all strong-variable, bona fide galactic LBVs, which present S-Dor-type variability. Strong-variable LBVs are located in a well-defined region of the HR diagram during visual minimum (the 'LBV minimum instability strip'). We suggest this region corresponds to where v{sub crit} is reached. To the left of this strip, a forbidden zone with v{sub rot}/v{sub crit}>1 is present, explaining why no LBVs are detected in this zone. Since dormant/ex LBVs like P Cygni and HD 168625 have low v{sub rot}, we propose that LBVs can be separated into two groups: fast-rotating, strong-variable stars showing S-Dor cycles (such as AG Car and HR Car) and slow-rotating stars with much less variability (such as P Cygni and HD 168625). We speculate that supernova (SN) progenitors which had S-Dor cycles before exploding (such as in SN 2001ig, SN 2003bg, and SN 2005gj) could have been fast rotators. We suggest that the potential difficulty of fast-rotating Galactic LBVs to lose angular momentum is additional evidence that such stars could explode during the LBV phase.

  13. Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall

    E-Print Network [OSTI]

    Analysis of Rotating Collectors from the Private Region of JET with Carbon Wall and Metallic ITER-Like Wall

  14. Properties of rotational bands at the spin limit in A $\\sim$ 50, A $\\sim$ 65 and A $\\sim$ 110 nuclei

    E-Print Network [OSTI]

    Janzen, V P; Andrews, H R; Ball, G C; Cameron, J A; Cromaz, M; DeGraaf, J; Flibotte, S; Galindo-Uribarri, A; Hackman, G; Headly, D M; Jonkman, J; Mullins, S M; Radford, D C; Ragnarsson, I; Rodríguez, J L; Svensson, C E; Waddington, J C; Ward, D; Zwartz, G

    1996-01-01T23:59:59.000Z

    Properties of rotational bands at the spin limit in A $\\sim$ 50, A $\\sim$ 65 and A $\\sim$ 110 nuclei

  15. Neutron Emission Spectroscopy of Fuel Ion Rotation and Fusion Power Components Demonstrated in the Trace Tritium Experiments at JET

    E-Print Network [OSTI]

    Neutron Emission Spectroscopy of Fuel Ion Rotation and Fusion Power Components Demonstrated in the Trace Tritium Experiments at JET

  16. Hydrodynamics of rapidly rotating superfluid neutron stars with mutual friction

    E-Print Network [OSTI]

    A. Passamonti; N. Andersson

    2010-04-26T23:59:59.000Z

    We study time evolutions of superfluid neutron stars, focussing on the nature of the oscillation spectrum, the effect of mutual friction force on the oscillations and the hydrodynamical spin-up phase of pulsar glitches. We linearise the dynamical equations of a Newtonian two-fluid model for rapidly rotating backgrounds. In the axisymmetric equilibrium configurations, the two fluid components corotate and are in beta-equilibrium. We use analytical equations of state that generate stratified and non-stratified stellar models, which enable us to study the coupling between the dynamical degrees of freedom of the system. By means of time evolutions of the linearised dynamical equations, we determine the spectrum of axisymmetric and non-axisymmetric oscillation modes, accounting for the contribution of the gravitational potential perturbations, i.e. without adopting the Cowling approximation. We study the mutual friction damping of the superfluid oscillations and consider the effects of the non-dissipative part of the mutual friction force on the mode frequencies. We also provide technical details and relevant tests for the hydrodynamical model of pulsar glitches discussed by Sidery, Passamonti and Andersson (2010). In particular, we describe the method used to generate the initial data that mimic the pre-glitch state, and derive the equations that are used to extract the gravitational-wave signal.

  17. Buoyancy and Penrose Process Produce Jets from Rotating Black Holes

    E-Print Network [OSTI]

    Semenov, V S; Heyn, M F

    2014-01-01T23:59:59.000Z

    The exact mechanism by which astrophysical jets are formed is still unknown. It is believed that necessary elements are a rotating (Kerr) black hole and a magnetised accreting plasma. We model the accreting plasma as a collection of magnetic flux tubes/strings. If such a tube falls into a Kerr black hole, then the leading portion loses angular momentum and energy as the string brakes, and to compensate for this loss, momentum and energy is redistributed to the trailing portion of the tube.} {We found that buoyancy creates a pronounced helical magnetic field structure aligned with the spin axis. Along the field lines, the plasma is centrifugally accelerated close to the speed of light. This process leads to unlimited stretching of the flux tube since one part of the tube continues to fall into the black hole and simultaneously the other part of the string is pushed outward. Eventually, reconnection cuts the tube, the inner part is filled with new material and the outer part forms a collimated bubble-structured...

  18. Three-dimensional airfoil performance measurements on a rotating wing

    SciTech Connect (OSTI)

    Butterfield, C.P.

    1989-06-01T23:59:59.000Z

    The objective of this comprehensive research program was to study the effects of horizontal-axis wind turbine (HAWT) blade rotation on aerodynamic behavior below, near, and beyond stall. This paper describes the flow angle sensor used to measure angle of attack (AOA) and how the sensor was calibrated, and it gives results of pressure integrations on the blade. Aerodynamic, load, flow-visualization, and inflow measurements were made on a 10-m, three-bladed, downwind HAWT. A video camera was mounted on the rotor to record video images of tufts attached to the low-pressure side of a constant-chord, zero-twist blade. Load measurements were made using strain gages mounted every 10% of the blade's span. Pressure taps were located at 32 chordwise positions and revealed pressure distributions comparable with wind tunnel data. Inflow was measured using a vertical-plane array of eight propvane and five triaxial (U-V-W) prop-type anemometers located 10 m upwind in the predominant wind direction. Results show evidence of stall hysteresis and unsteadiness at high AOA. Correlations with analytical predictions and wind tunnel tests show good agreement at low AOA and poor agreement at high AOA. 7 refs., 12 figs.

  19. Muon spin rotation studies of niobium for superconducting RF applications

    E-Print Network [OSTI]

    Grassellino, A; Kolb, P; Laxdal, R; Lockyer, N S; Longuevergne, D; Sonier, J E

    2013-01-01T23:59:59.000Z

    In this work we investigate superconducting properties of niobium samples via application of the muon spin rotation/relaxation (muSR) technique. We employ for the first time the muSR technique to study samples that are cutout from large and small grain 1.5 GHz radio frequency (RF) single cell niobium cavities. The RF test of these cavities was accompanied by full temperature mapping to characterize the RF losses in each of the samples. Results of the muSR measurements show that standard cavity surface treatments like mild baking and buffered chemical polishing (BCP) performed on the studied samples affect their surface pinning strength. We find an interesting correlation between high field RF losses and field dependence of the sample magnetic volume fraction measured via muSR. The muSR line width observed in ZF-muSR measurements matches the behavior of Nb samples doped with minute amounts of Ta or N impurities. An upper bound for the upper critical field Hc2 of these cutouts is found.

  20. The Rotating Dyonic Black Holes Of Kaluza-Klein Theory

    E-Print Network [OSTI]

    Dean Rasheed

    1995-05-06T23:59:59.000Z

    The most general electrically and magnetically charged rotating black hole solutions of 5 dimensional \\KK\\ theory are given in an explicit form. Various classical quantities associated with the black holes are derived. In particular, one finds the very surprising result that the gyromagnetic and gyroelectric ratios can become {\\tenit arbitrarily large}. The thermodynamic quantities of the black holes are calculated and a Smarr-type formula is obtained leading to a generalized first law of black hole thermodynamics. The properties of the extreme solutions are investigated and it is shown how they naturally separate into two classes. The extreme solutions in one class are found to have two unusual properties: (i). Their event horizons have zero angular velocity and yet they have non-zero ADM angular momentum. (ii). In certain circumstances it is possible to add angular momentum to these extreme solutions without changing the mass or charges and yet still maintain an extreme solution. Regarding the extreme black holes as elementary particles, their stability is discussed and it is found that they are stable provided they have sufficient angular momentum.

  1. On the Doppler effect for photons in rotating systems

    E-Print Network [OSTI]

    Giuliani, Giuseppe

    2015-01-01T23:59:59.000Z

    The analysis of the Doppler effect for photons in rotating systems, studied using the M\\"ossbauer effect, confirms the general conclusions of a previous paper dedicated to experiments with photons emitted/absorbed by atoms/nuclei in inertial flight. The wave theory of light is so deeply rooted that it has been--and currently is--applied to describe phenomena in which the fundamental entities at work are discrete (photons). The fact that the wave theory of light can describe one aspect of these phenomena can not overshadow two issues: the corpuscular theory of light, firstly applied to the Doppler effect for photons by Schr\\"odinger in 1922, is by far more complete since it describes all the features of the studied phenomena; the wave theory can be used only when the number of photons at work is statistically significant. The disregard of basic methodological criteria may appear as a minor fault. However, the historical development of quantum physics shows that the predominance of the wave theory of radiation,...

  2. Measuring the rotation period distribution of field M-dwarfs with Kepler

    E-Print Network [OSTI]

    McQuillan, Amy; Mazeh, Tsevi

    2013-01-01T23:59:59.000Z

    We have analysed 10 months of public data from the Kepler space mission to measure rotation periods of main-sequence stars with masses between 0.3 and 0.55 M_sun. To derive the rotational period we introduce the autocorrelation function and show that it is robust against phase and amplitude modulation and residual instrumental systematics. Of the 2483 stars examined, we detected rotation periods in 1570 (63.2%), representing an increase of a factor ~ 30 in the number of rotation period determination for field M-dwarfs. The periods range from 0.37-69.7 days, with amplitudes ranging from 1.0-140.8 mmags. The rotation period distribution is clearly bimodal, with peaks at ~ 19 and ~ 33 days, hinting at two distinct waves of star formation, a hypothesis that is supported by the fact that slower rotators tend to have larger proper motions. The two peaks of the rotation period distribution form two distinct sequences in period-temperature space, with the period decreasing with increasing temperature, reminiscent of ...

  3. FURTHER RESULTS FROM THE GALACTIC O-STAR SPECTROSCOPIC SURVEY: RAPIDLY ROTATING LATE ON GIANTS

    SciTech Connect (OSTI)

    Walborn, Nolan R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); MaIz Apellaniz, Jesus; Sota, Alfredo; Alfaro, Emilio J. [Instituto de Astrofisica de Andalucia-CSIC, Glorieta de la Astronomia s/n, 18008 Granada (Spain); Morrell, Nidia I. [Las Campanas Observatory, Observatories of the Carnegie Institution of Washington, Casilla 601, La Serena (Chile); Barba, Rodolfo H.; Arias, Julia I. [Departamento de Fisica, Universidad de La Serena, Cisternas 1200 Norte, La Serena (Chile); Gamen, Roberto C., E-mail: walborn@stsci.edu, E-mail: jmaiz@iaa.es, E-mail: sota@iaa.es, E-mail: emilio@iaa.es, E-mail: nmorrell@lco.cl, E-mail: rbarba@dfuls.cl, E-mail: julia@dfuls.cl, E-mail: rgamen@fcaglp.unlp.edu.ar [Instituto de Astrofisica de La Plata-CONICET and Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata (Argentina)

    2011-11-15T23:59:59.000Z

    With new data from the Galactic O-Star Spectroscopic Survey, we confirm and expand the ONn category of late-O, nitrogen-enriched (N), rapidly rotating (n) giants. In particular, we have discovered two 'clones' (HD 102415 and HD 117490) of one of the most rapidly rotating O stars previously known (HD 191423, 'Howarth's Star'). We compare the locations of these objects in the theoretical H-R diagram to those of slowly rotating ON dwarfs and supergiants. All ON giants known to date are rapid rotators, whereas no ON dwarf or supergiant is, but all ON stars are small fractions of their respective spectral-type/luminosity-class/rotational subcategories. The ONn giants, displaying both substantial processed material and high rotation at an intermediate evolutionary stage, may provide significant information about the development of these properties. They may have preserved high initial rotational velocities or may have been spun up by terminal-age main-sequence core contraction; alternatively, and perhaps more likely, they may be products of binary mass transfer. At least some of them are also runaway stars.

  4. Simulation of Non-resonant Internal Kink Mode with Toroidal Rotation in NSTX

    SciTech Connect (OSTI)

    Fu, Guoyong

    2013-07-16T23:59:59.000Z

    Plasmas in spherical and conventional tokamaks, with weakly reversed shear q pro le and minimum q above but close to unity, are susceptible to an non-resonant (m, n ) = (1, 1) internal kink mode. This mode can saturate and persist and can induce a (2; 1) seed island for Neoclassical Tearing Mode (NTMs)1 . The mode can also lead to large energetic particle transport and signi cant broadening of beam-driven current. Motivated by these important e ects, we have carried out extensive nonlinear simulations of the mode with nite toroidal rotation using parameters and pro les of an NTSX plasma with a weakly reversed shear pro le. The numerical results show that, at the experimental level, plasma rotation has little e ect on either equilibrium or linear stability. However, rotation can signi cantly inuence the nonlinear dynamics of the (1, 1) mode and the the induced (2, 1) magnetic island. The simulation results show that a rotating helical equilibrium is formed and maintained in the nonlinear phase at nite plasma rotation. In contrast, for non-rotating cases, the nonlinear evolution exhibits dynamic oscillations between a quasi-2D state and a helical state. Furthermore, the e ects of rotation are found to greatly suppress the (2, 1) magnetic island even at a low level.

  5. The role of short-rotation woody crops in sustainable development

    SciTech Connect (OSTI)

    Shepard, J.P. [National Council of the Paper Industry for Air and Stream Improvement, Medford, MA (United States); Tolbert, V.R. [Oak Ridge National Lab., TN (United States)

    1996-12-31T23:59:59.000Z

    One answer to increase wood production is by increasing management intensity on existing timberland, especially in plantation forests. Another is to convert land currently in agriculture to timberland. Short-rotation woody crops can be used in both cases. But, what are the environmental consequences? Short-rotation woody crops can provide a net improvement in environmental quality at both local and global scales. Conversion of agricultural land to short-rotation woody crops can provide the most environmental quality enhancement by reducing erosion, improving soil quality, decreasing runoff, improving groundwater quality, and providing better wildlife habitat. Forest products companies can use increased production from intensively managed short-rotation woody crop systems to offset decreased yield from the portion of their timberland that is managed less intensively, e.g. streamside management zones and other ecologically sensitive or unique areas. At the global scale, use of short-rotation woody crops for bioenergy is part of the solution to reduce greenhouse gases produced by burning fossil fuels. Incorporating short-rotation woody crops into the agricultural landscape also increases storage of carbon in the soil, thus reducing atmospheric concentrations. In addition, use of wood instead of alternatives such as steel, concrete, and plastics generally consumes less energy and produces less greenhouse gases. Cooperative research can be used to achieve energy, fiber, and environmental goals. This paper will highlight several examples of ongoing cooperative research projects that seek to enhance the environmental aspects of short-rotation woody crop systems. Government, industry, and academia are conducting research to study soil quality, use of mill residuals, nutrients in runoff and groundwater, and wildlife use of short-rotation woody crop systems in order to assure the role of short-rotation crops as a sustainable way of meeting society`s needs.

  6. Sensitivity analysis of the solar rotation to helioseismic data from GONG, GOLF and MDI observations

    E-Print Network [OSTI]

    A. Eff-Darwich; S. G. Korzennik; S. J. Jimenez-Reyes; R. A. Garcia

    2008-02-25T23:59:59.000Z

    Accurate determination of the rotation rate in the radiative zone of the sun from helioseismic observations requires rotational frequency splittings of exceptional quality as well as reliable inversion techniques. We present here inferences based on mode parameters calculated from 2088-days long MDI, GONG and GOLF time series that were fitted to estimate very low frequency rotational splittings (nu < 1.7 mHz). These low frequency modes provide data of exceptional quality, since the width of the mode peaks is much smaller than the rotational splitting and hence it is much easier to separate the rotational splittings from the effects caused by the finite lifetime and the stochastic excitation of the modes. We also have implemented a new inversion methodology that allows us to infer the rotation rate of the radiative interior from mode sets that span l=1 to 25. Our results are compatible with the sun rotating like a rigid solid in most of the radiative zone and slowing down in the core (R_sun < 0.2). A resolution analysis of the inversion was carried out for the solar rotation inverse problem. This analysis effectively establishes a direct relationship between the mode set included in the inversion and the sensitivity and information content of the resulting inferences. We show that such an approach allows us to determine the effect of adding low frequency and low degree p-modes, high frequency and low degree p-modes, as well as some g-modes on the derived rotation rate in the solar radiative zone, and in particular the solar core. We conclude that the level of uncertainties that is needed to infer the dynamical conditions in the core when only p-modes are included is unlikely to be reached in the near future, and hence sustained efforts are needed towards the detection and characterization of g-modes.

  7. Wave Properties of Plasma Surrounding the Event Horizon of a Non-Rotating Black Hole

    E-Print Network [OSTI]

    M. Sharif; G. Mustafa

    2008-09-09T23:59:59.000Z

    We have studied the wave properties of the cold and isothermal plasma in the vicinity of the Schwarzschild black hole event horizon. The Fourier analyzed perturbed 3+1 GRMHD equations are taken on the basis of which the complex dispersion relations are obtained for non-rotating, rotating non-magnetized and rotating magnetized backgrounds. The propagation and attenuation vectors along with the refractive index are obtained (shown in graphs) to study the dispersive properties of the medium near the event horizon. The results show that no information can be obtained from the Schwarzschild magnetosphere. Further, the pressure ceases the existence of normal dispersion of waves.

  8. Rotational Augmentation Disparities in the MEXICO and UAE Phase VI Experiments: Preprint

    SciTech Connect (OSTI)

    Schreck, S.; Sant, T.; Micallef, D.

    2010-05-01T23:59:59.000Z

    Wind turbine structures and components suffer excessive loads and premature failures when key aerodynamic phenomena are not well characterized, fail to be understood, or are inaccurately predicted. Turbine blade rotational augmentation remains incompletely characterized and understood, thus limiting robust prediction for design. Pertinent rotational augmentation research including experimental, theoretical, and computational work has been pursued for some time, but large scale wind tunnel testing is a relatively recent development for investigating wind turbine blade aerodynamics. Because of their large scale and complementary nature, the MEXICO and UAE Phase VI wind tunnel experiments offer unprecedented synergies to better characterize and understand rotational augmentation of blade aerodynamics.

  9. Phase-kicked control of counter-rotating interactions in the quantum Rabi model

    E-Print Network [OSTI]

    Jin-Feng Huang; C. K. Law

    2014-07-17T23:59:59.000Z

    We present an interaction scheme to control counter-rotating terms in the quantum Rabi model. We show that by applying a sequence of $\\pi/2$ phase kicks to a two-level atom and a single mode quantized field, the natural dynamics of the Rabi model can be interrupted in a way that counter-rotating transitions can be significantly enhanced. This is achieved by a suitable timing of the phase kicks determined by a phase matching condition. If the time between successive kicks is sufficiently short, our scheme is turned into a dynamical decoupling problem in which the effects of counter-rotating terms can be strongly suppressed under ultrastrong coupling.

  10. Managing lodgepole pine to yield merchantable thinning products and attain sawtimber rotations. Forest Service research paper

    SciTech Connect (OSTI)

    Cole, D.M.; Koch, P.

    1995-12-01T23:59:59.000Z

    This paper suggests solution for a longstanding problem in managing lodgepole pine forests- that of managing individual stands to reach their planned rotation age, despite serious hazard from bark beetles and wildfire. The management regimes presented yield merchantable thinning products. The 80-year sawtimber rotation can be achieved using these management recommendation. Thinning at 30 years of age is central to achieving the recommended alternative management regimes. The authors suggest that agencies give roundwood operators a portion of the thinning stemwood as payment. Management regimes that provide attainable rotations are presented in summary tables, by three site index classes and a number of initial stand density classes.

  11. Controlling the collimation and rotation of hydromagnetic disk winds

    E-Print Network [OSTI]

    Ralph E. Pudritz; Conrad Rogers; Rachid Ouyed

    2005-08-12T23:59:59.000Z

    (Abriged) We present a comprehensive set of axisymmetric, time-dependent simulations of jets from Keplerian disks whose mass loading as a function of disk radius is systematically changed. For a reasonable model for the density structure and injection speed of the underlying accretion disk, mass loading is determined by the radial structure of the disk's magnetic field structure. We vary this structure by using four different magnetic field configurations, ranging from the "potential" configuration (Ouyed&Pudritz 1997), to the increasingly more steeply falling Blandford&Payne (1982) and Pelletier&Pudritz (1992) models, and ending with a quite steeply raked configuration that bears similarities to the Shu X-wind model. We find that the radial distribution of the mass load has a profound effect on both the rotational profile of the underlying jet as well as the degree of collimation of its outflow velocity and magnetic field lines. We show analytically, and confirm by our simulations, that the collimation of a jet depends on its radial current distribution, which in turn is prescribed by the mass load. Models with steeply descending mass loads have strong toroidal fields, and these collimate to cylinders (this includes the Ouyed-Pudritz and Blandford-Payne outflows). On the other hand, the more gradually descending mass load profiles (the PP92 and monopolar distributions) have weaker toroidal fields, and these result in wide-angle outflows with parabolic collimation. We also present detailed structural information about jets such as their radial profiles of jet density, toroidal magnetic field, and poloidal jet speed, as well as an analysis of the bulk energetics of our different simulations.

  12. Design and operation of a counter-rotating aspirated compressor blowdown test facility

    E-Print Network [OSTI]

    Parker, David V. (David Vickery)

    2005-01-01T23:59:59.000Z

    A unique counter-rotating aspirated compressor was tested in a blowdown facility at the Gas Turbine Laboratory at MIT. The facility expanded on experience from previous blowdown turbine and blowdown compressor experiments. ...

  13. Spatio-temporal theory of lasing action in optically-pumped rotationally excited molecular gases

    E-Print Network [OSTI]

    Chua, Song-Liang

    We investigate laser emission from optically-pumped rotationally excited molecular gases confined in a metallic cavity. To this end, we have developed a theoretical framework able to accurately describe, both in the spatial ...

  14. A two-phase spherical electric machine for generating rotating uniform magnetic fields

    E-Print Network [OSTI]

    Lawler, Clinton T. (Clinton Thomas)

    2007-01-01T23:59:59.000Z

    This thesis describes the design and construction of a novel two-phase spherical electric machine that generates rotating uniform magnetic fields, known as a fluxball machine. Alternative methods for producing uniform ...

  15. Effects of demagnetizing factors on transient motion of ferrofluid in a uniform rotating magnetic field

    E-Print Network [OSTI]

    Snively, Michael John

    2011-01-01T23:59:59.000Z

    The mechanisms that lead to bulk flow within a ferrofluid-filled container subjected to a rotating uniform magnetic field are experimentally studied. There are two prevailing theories: spin diffusion theory and flow due ...

  16. Analogies of Ocean/Atmosphere Rotating Fluid Dynamics with Gyroscopes: Teaching Opportunities

    E-Print Network [OSTI]

    Haine, Thomas W. N.

    The dynamics of the rotating shallow-water (RSW) system include geostrophic f low and inertial oscillation. These classes of motion are ubiquitous in the ocean and atmosphere. They are often surprising to people at first ...

  17. Perturbation of the ns energy levels of the hydrogen atom in rotationally invariant noncommutative space

    E-Print Network [OSTI]

    Kh. P. Gnatenko; Yu. S. Krynytskyi; V. M. Tkachuk

    2014-12-23T23:59:59.000Z

    Noncommutative space which is rotationally invariant is considered. The hydrogen atom is studied in this space. We exactly find the leading term in the asymptotic expansion of the corrections to the $ns$ energy levels over the small parameter of noncommutativity.

  18. 5D Einstein-Maxwell solitons and concentric rotating dipole black rings

    E-Print Network [OSTI]

    Stoytcho Yazadjiev

    2008-05-12T23:59:59.000Z

    We discuss the application of the solitonic techniques to the 5D Einstein-Maxwell gravity. As an illustration we construct an exact solution describing two concentric rotating dipole black rings. The properties of the solution are investigated.

  19. Energy Loss Distribution in the Taylor-Couette Flow between Concentric Rotating Cylinders

    E-Print Network [OSTI]

    Dou, H S; Phan-Thien, N; Yeo, K S; Dou, Hua-Shu; Khoo, Boo Cheong; Phan-Thien, Nhan; Yeo, Khoon Seng

    2005-01-01T23:59:59.000Z

    The distribution of energy loss due to viscosity friction in plane Couette flow and Taylor-Couette Flow between concentric rotating cylinders are studied in detail for various flow conditions. The energy loss is related to the industrial processes in some fluid delivery devices and has significant influence on the flow efficiency, flow stability, turbulent transition, mixing, and heat transfer behaviours, etc. Therefore, it is very helpful to know about the energy loss distribution in the flow domain and to know its influence on the flow for understanding the flow physics. The calculation method of the energy loss distribution in the Taylor-Couette Flow between concentric rotating cylinders has not been found in open literature. In this note, the principle and the calculation are given for single cylinder rotating of inner or outer cylinder, and counter and same direction rotating of two cylinders. For comparison, the distribution of energy loss in a plane Couette flow is also derived for various flow conditi...

  20. Parent Stars of Extrasolar Planets. XV. Host Star Rotation Revisited with {\\it Kepler} Data

    E-Print Network [OSTI]

    Gonzalez, Guillermo

    2015-01-01T23:59:59.000Z

    We employed published rotation periods of {\\it Kepler} field stars to test whether stars hosting planets tend to rotate more slowly than stars without known planets. Spectroscopic vsini observations of nearby stars with planets have indicated that they tend to have smaller visni values. We employ data for {\\it Kepler} Objects of Interest (KOIs) from the first 16 quarters of its original mission; stellar parameters are based on the analysis of the first 17 quarters. We confirm that KOI stars rotate more slowly with much greater confidence than we had previously found for nearby stars with planets. Furthermore, we find that stars with planets of all types rotate more slowly, not just stars with giant planets.

  1. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

    2011-11-15T23:59:59.000Z

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  2. Low torque hydrodynamic lip geometry for bi-directional rotation seals

    DOE Patents [OSTI]

    Dietle, Lannie L. (Houston, TX); Schroeder, John E. (Richmond, TX)

    2009-07-21T23:59:59.000Z

    A hydrodynamically lubricating geometry for the generally circular dynamic sealing lip of rotary seals that are employed to partition a lubricant from an environment. The dynamic sealing lip is provided for establishing compressed sealing engagement with a relatively rotatable surface, and for wedging a film of lubricating fluid into the interface between the dynamic sealing lip and the relatively rotatable surface in response to relative rotation that may occur in the clockwise or the counter-clockwise direction. A wave form incorporating an elongated dimple provides the gradual convergence, efficient impingement angle, and gradual interfacial contact pressure rise that are conducive to efficient hydrodynamic wedging. Skewed elevated contact pressure zones produced by compression edge effects provide for controlled lubricant movement within the dynamic sealing interface between the seal and the relatively rotatable surface, producing enhanced lubrication and low running torque.

  3. Rotational-Vibrational Raman Spectroscopy for Measurements of Thermochemistry in Non-isobaric Environments

    E-Print Network [OSTI]

    Bayeh, Alexander C.

    2010-01-14T23:59:59.000Z

    The present work examines line measurements of pressure, temperature, and density in high speed, non-isobaric flows emanating from an underexpanded jet nozzle. Line images of rotational and vibrational Raman spectra are collected for a 8-mm linear...

  4. Perturbation of the ns energy levels of the hydrogen atom in rotationally invariant noncommutative space

    E-Print Network [OSTI]

    Gnatenko, Kh P; Tkachuk, V M

    2014-01-01T23:59:59.000Z

    Noncommutative space which is rotationally invariant is considered. The hydrogen atom is studied in this space. We exactly find the leading term in the asymptotic expansion of the corrections to the $ns$ energy levels over the small parameter of noncommutativity.

  5. NON-GAUSSIAN STATISTICS AND STELLAR ROTATIONAL VELOCITIES OF MAIN-SEQUENCE FIELD STARS

    SciTech Connect (OSTI)

    Carvalho, J. C.; Do Nascimento, J. D.; Silva, R.; De Medeiros, J. R. [Universidade Federal do Rio Grande do Norte, UFRN, Departamento de Fisica, C. P. 1641, Natal, RN 59072-970 (Brazil)

    2009-05-01T23:59:59.000Z

    In this Letter, we study the observed distributions of rotational velocity in a sample of more than 16,000 nearby F and G dwarf stars, magnitude complete, and presenting high-precision Vsin i measurements. We show that the velocity distributions cannot be fitted by a Maxwellian. In addition, an analysis based on both Tsallis and Kaniadakis power-law statistics is by far the most appropriate statistics and gives a very good fit. It is also shown that single and binary stars have similar rotational distributions. This is the first time, to our knowledge, that these two new statistics have been tested for the rotation of such a large sample of stars, pointing solidly to a solution of the puzzling problem of the function governing the distribution of stellar rotational velocity.

  6. Principles and biophysical applications of single particle super-localization and rotational tracking

    SciTech Connect (OSTI)

    Gu, Yan [Ames Laboratory

    2013-05-15T23:59:59.000Z

    While conventional Single Particle Tracking (SPT) techniques acquire 2D or 3D trajectories of particle probes, we have developed Single Particle Orientation and Rotational Tracking (SPORT) techniques to extract orientation and rotational information. Combined with DIC microscopy, the SPORT technique has been applied in biophysical studies, including membrane diffusion and intracellular transport. The rotational dynamics of nanoparticle vectors on live cell membranes was recorded and its influence on the fate of these nanoparticle vectors was elucidated. The rotational motions of gold nanorods with various surface modifiers were tracked continuously at a temporal resolution of 5 ms under a DIC microscope. We found that the rotational behaviors of gold nanorod vectors are strongly related to their surface charge, specific surface functional groups, and the availability of receptors on cell membranes. The study of rotational Brownian motion of nanoparticles on cell membranes will lead to a better understanding of the mechanisms of drug delivery and provide guidance in designing surface modification strategies for drug delivery vectors under various circumstances. To characterize the rotation mode of surface functionalized gold nanorods on cell membranes, the SPORT technique is combined with the correlation analysis of the bright and dark DIC intensities. The unique capabilities of visualizing and understanding rotational motions of functionalized nanoparticles on live cell membranes allow us to correlate rotational and translational dynamics in unprecedented detail and provide new insights for complex membrane processes, including electrostatic interactions, ligand-receptor binding, and lateral (confined and hopping) diffusion of membrane receptors. Surface-functionalized nanoparticles interact with the membrane in fundamentally different ways and exhibit distinct rotational modes. The early events of particle-membrane approach and attachment are directly visualized for the first time. The rotational dynamics of cargos in both active directional transport and pausing stages of axonal transport was also visualized using high-speed SPORT with a temporal resolution of 2 ms. Both long and short pauses are imaged, and the correlations between the pause duration, the rotational behaviour of the cargo at the pause, and the moving direction after the pause are established. Furthermore, the rotational dynamics leading to switching tracks are visualized in detail. These first-time observations of cargo's rotational dynamics provide new insights on how kinesin and dynein motors take the cargo through the alternating stages of active directional transport and pause. To improve the localization precision of the SPT technique with DIC microscopy, a precise three-dimensional (3D) localization method of spherical gold nanoparticle probes using model-based correlation coefficient mapping was introduced. To accomplish this, a stack of sample images at different z-positions are acquired, and a 3D intensity profile of the probe serving as the model is used to map out the positions of nanoparticles in the sample. By using this model-based correlation imaging method, precise localization can be achieved in imaging techniques with complicated point spread functions (PSF) such as differential interference contrast (DIC) microscopy. The 3D superlocalization method was applied to tracking gold nanospheres during live endocytosis events. Finally, a novel dual-modality imaging technique has been developed to super-localize a single gold nanorod while providing its orientation and rotational information. The super-localization of the gold nanorod can be accomplished by curve fitting the modified bright-field images generated by one of the two beams laterally shifted by the first Nomarski prism in a DIC microscope. The orientation and rotational information is derived from the DIC images of gold nanorods. The new imaging setup has been applied to study the steric hindrance induced by relatively large cargos in the microtubule gliding assay and to track

  7. Vibrational characteristics of a long and very flexible rotating fixed-free beam

    E-Print Network [OSTI]

    Zarco Cruz, Juan Carlos

    2003-01-01T23:59:59.000Z

    The differential eigenvalue problem of a long and very flexible rotating fixed-free beam is studied. This kind of system produces a singular perturbation equation with a turning point. The perturbation factor arises because of the division...

  8. Global Existence and Long-Time Asymptotics for Rotating Fluids in a 3D layer

    E-Print Network [OSTI]

    Gallay, Thierry

    Global Existence and Long-Time Asymptotics for Rotating Fluids in a 3D layer Thierry Gallay thierry.gallay@ujf-grenoble.fr Violaine Roussier-Michon Institut de Math´ematiques de Toulouse (UMR CNRS

  9. Global Existence and LongTime Asymptotics for Rotating Fluids in a 3D layer

    E-Print Network [OSTI]

    Gallay, Thierry

    Global Existence and Long­Time Asymptotics for Rotating Fluids in a 3D layer Thierry Gallay thierry.gallay@ujf­grenoble.fr Violaine Roussier­Michon Institut de Mathâ??ematiques de Toulouse (UMR CNRS

  10. Measurements of the Solid-body Rotation of Anisotropic Particles in 3D Turbulence

    E-Print Network [OSTI]

    Marcus, Guy G; Kramel, Stefan; Ni, Rui; Voth, Greg A

    2014-01-01T23:59:59.000Z

    We introduce a new method to measure Lagrangian vorticity and the rotational dynamics of anisotropic particles in a turbulent fluid flow. We use 3D printing technology to fabricate crosses (two perpendicular rods) and jacks (three mutually perpendicular rods). Time-resolved measurements of their orientation and solid-body rotation rate are obtained from stereoscopic video images of their motion in a turbulent flow between oscillating grids with $R_\\lambda$=$91$. The advected particles have a largest dimension of 6 times the Kolmogorov length, making them a good approximation to anisotropic tracer particles. Crosses rotate like disks and jacks rotate like spheres, so these measurements, combined with previous measurements of tracer rods, allow experimental study of ellipsoids across the full range of aspect ratios. The measured mean square tumbling rate, $\\langle \\dot{p}_i \\dot{p}_i \\rangle$, confirms previous direct numerical simulations that indicate that disks tumble much more rapidly than rods. Measurement...

  11. Zero-point fluctuations in rotation: Perpetuum mobile of the fourth kind without energy transfer

    E-Print Network [OSTI]

    M. N. Chernodub

    2013-02-03T23:59:59.000Z

    We discuss a simple Casimir-type device for which the rotational energy reaches its global minimum when the device rotates about a certain axis rather than remains static. This unusual property is a direct consequence of the fact that the moment of inertia of zero-point vacuum fluctuations is a negative quantity (the rotational vacuum effect). Moreover, the device does not produce any work despite the fact that its equilibrium ground state corresponds to a permanent rotation. Counterintuitively, the device has no internally moving mechanical parts while its very existence is consistent with the laws of thermodynamics. We point out that such devices may possibly be constructed using carbon nanotubes. We call this "zero-point-driven" device as the perpetuum mobile of the fourth kind.

  12. Mechanical design of a contra-rotating propeller assembly for a small underwater ROV

    E-Print Network [OSTI]

    Stefanov-Wagner, Thaddeus (Thaddeus J.)

    2006-01-01T23:59:59.000Z

    A project was undertaken to design and build a contra-rotating propeller assembly for a small underwater remotely operated vehicle (ROV), with the intent of commissioning a production run at a later time. The desired ...

  13. Numerical Study of Geometry and Rotation Dependence on the Flow in Labyrinth Seals 

    E-Print Network [OSTI]

    Yamsani, Vamshi Krishna

    2011-10-21T23:59:59.000Z

    A computational study was conducted on the flow, both compressible and incompressible, in a labyrinth seal at various geometries and rotation rates. The computations were performed using the commercial software Fluent® which solves the k-? model...

  14. Primary crossflow vortices, secondary absolute instabilities and their control in the rotating-disk boundary layer

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Primary crossflow vortices, secondary absolute instabilities and their control in the rotating patterns of crossflow vortices are derived by employing asymptotic techniques. This approach accounts three-dimensional velocity profiles, are subject to inviscid crossflow in- stabilities and rapidly

  15. M-DWARF RAPID ROTATORS AND THE DETECTION OF RELATIVELY YOUNG MULTIPLE M-STAR SYSTEMS

    E-Print Network [OSTI]

    Swift, J.

    We have searched the Kepler light curves of ~3900 M-star targets for evidence of periodicities that indicate, by means of the effects of starspots, rapid stellar rotation. Several analysis techniques, including Fourier ...

  16. Two-Dimensional Image Rotation Ivan Sterling 1 and Thomas Sterling 2

    E-Print Network [OSTI]

    Sterling, Ivan

    Two-Dimensional Image Rotation Ivan Sterling 1 and Thomas Sterling 2 1 Department of Mathematics scanning of a document, such as an engineering drawing. When the drawing is fed into the scanner, it may

  17. Design of compliant mechanisms for attenuation of unidirectional vibrations in rotational systems

    E-Print Network [OSTI]

    Szczesny, Spencer E., 1981-

    2005-01-01T23:59:59.000Z

    The purpose of this research was to generate the knowledge required to design compliant mechanisms that (1) attenuate undesired small-motion angular vibrations in rotational power transmission systems and (2) preserve the ...

  18. The effective geometry of the $n=1$ uniformly rotating self-gravitating polytrope

    E-Print Network [OSTI]

    Donato Bini; Christian Cherubini; Simonetta Filippi; Andrea Geralico

    2014-08-20T23:59:59.000Z

    The \\lq\\lq effective geometry" formalism is used to study the perturbations of a perfect barotropic Newtonian self-gravitating rotating and compressible fluid coupled with gravitational backreaction. The case of a uniformly rotating polytrope with index $n=1$ is investigated, due to its analytical tractability. Special attention is devoted to the geometrical properties of the underlying background acoustic metric, focusing in particular on null geodesics as well as on the analog light cone structure.

  19. Absolute measurement of the viscosity of classical and quantum fluids by rotating-cylinder viscometers

    SciTech Connect (OSTI)

    Donnelly, R.J.; LaMar, M.M.

    1987-11-01T23:59:59.000Z

    We discuss the use of rotating-cylinder viscometers to determine absolute shear viscosities of classical fluids and of helium II in the context of past and current knowledge of the stability and flow of these fluids between concentric cylinders. We identify a problem in measuring the absolute viscosity when the inner cylinder is rotating and the outer cylinder is at rest. We conclude by discussing the design of viscometers for absolute viscosity measurements in helium I and helium II.

  20. A numerical method for the design and analysis of counter-rotating propellers

    E-Print Network [OSTI]

    Playle, Scott Charles

    1984-01-01T23:59:59.000Z

    -Rotating Propellers from Airfoil Characteristics", NACA ARR 3EZ4 (WR L-330), May 1943. 13. Davidson, R. E. , "Optimization and Performance Calculation of Dual-Rotation Propellers", NASA TP 1948, December 1981. 14. Theodorsen, T. , "The Theory of Propellers... 1. Design Flight Conditions 2. Propeller Performance from Naiman and Davidson Design Methods 3. Efficiency Characteristics of the Three Propeller Designs 4. Thrust Coefficients of the Three Propeller Designs 5. Power Coefficients of the Three...

  1. Factors affecting weaning weights of calves produced in Hereford and rotational crossbred herds

    E-Print Network [OSTI]

    Tovar-Rodriguez, Jorge

    1965-01-01T23:59:59.000Z

    FACTORS AFFECTING WEANING WEIGHTS OF CALVES PRODUCED IN HEREFORD AND ROTATIONAL CROSSBRED HERDS A Thesis By jORGE TOVAR R. Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1965 Major Subject: Animal Production FACTORS AFFECTING WEANING WEIGHTS OF CALVES PRODUCED IN HEREFORD AND ROTATIONAL CROSSBRED HERDS A Thesis By JORGE TOVAR R. Approved as to style an content by: ( ' an of Committee...

  2. A mathematical model for the electrodeposition of amorphous alloys on a rotating disk electrode

    E-Print Network [OSTI]

    Chen, Shiuan

    1986-01-01T23:59:59.000Z

    A MATHEMATICAL MODEL FOR THE ELECTRODEPOSITION OF AMORPHOUS ALLOYS ON A ROTATING DISK ELECTRODE A Thesis by SHIUAN CHEN Submitted to the Graduate College of Texas AAcM University in partial fulfillment of the requirement, for the degree... of MASTER OF SCIENCE December 19B6 Major Subject: Chemical Engineering A MATHEMATICAL MODEL FOR THE ELECTRODEPOSITION OF AMORPHOUS ALLOYS ON A ROTATING DISK ELECTRODE A Thesis by SHIUAN CHEN Approved as to style and content by: alph E. White...

  3. Neutrino transport and hydrodynamic stability of rotating proto-neutron stars

    E-Print Network [OSTI]

    V. Urpin

    2007-04-24T23:59:59.000Z

    We consider stability of differentially rotating non-magnetic proto-neutron stars. When neutrino transport is efficient, the star can be subject to a diffusive instability that can occur even in the convectively stable region. The instability arises on the time-scale comparable to the time-scale of thermal diffusion. Hydrodynamic motions driven by the instability can lead to anisotropy in the neutrino flux since the instability is suppressed near the equator and rotation axis.

  4. Analysis and experimental study of a plate-type hydraulic vibration damper for cryogenic rotating machinery

    E-Print Network [OSTI]

    Olan, Emmanuel Angustia

    1991-01-01T23:59:59.000Z

    ANALYSIS AND EXPERIMENTAL STUDY OF A PLATE-TYPE HYDRAULIC VIBRATION DAMPER FOR CRYOGENIC ROTATING MACHINERY A Thesis by EMMANUEL ANGUSTIA OLAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1991 Major Subject: Mechanical Engineering ANALYSIS AND EXPERIMENTAL STUDY OF A PLATE-TYPE HYDRAULIC VIBRATION DAMPER FOR CRYOGENIC ROTATING MACHINERY A Thesis by EMMANUEL ANGUSTIA OLAN Approved...

  5. On Rotating and Oscillating Four-Spin Strings in AdS5 X S5

    E-Print Network [OSTI]

    Kamal L. Panigrahi; Pabitra M. Pradhan

    2012-10-26T23:59:59.000Z

    We study rigidly rotating strings in AdS5 X S5 background with one spin along AdS5 and three angular momenta along S5. We find dispersion relations among various charges and interpret them as giant magnon and spiky string solutions in various limits. Further we present an example of oscillating string which oscillates in the radial direction of the AdS5 and at the same time rotates in S5.

  6. On Rotating and Oscillating Four-Spin Strings in AdS5 X S5

    E-Print Network [OSTI]

    Panigrahi, Kamal L

    2012-01-01T23:59:59.000Z

    We study rigidly rotating strings in AdS5 X S5 background with one spin along AdS5 and three angular momenta along S5. We find dispersion relations among various charges and interpret them as giant magnon and spiky string solutions in various limits. Further we present an example of oscillating string which oscillates in the radial direction of the AdS5 and at the same time rotates in S5.

  7. Geometric Phase Of The Faraday Rotation Of Electromagnetic Waves In Magnetized Plasma

    SciTech Connect (OSTI)

    Jian Liu and Hong Qin

    2011-11-07T23:59:59.000Z

    The geometric phase of circularly polarized electromagnetic waves in nonuniform magnetized plasmas is studied theoretically. The variation of the propagation direction of circularly polarized waves results in a geometric phase, which also contributes to the Faraday rotation, in addition to the standard dynamical phase. The origin and properties of the geometric phase is investigated. The in uence of the geometric phase to plasma diagnostics using Faraday rotation is also discussed as an application of the theory.

  8. Apparatus and method for generating a magnetic field by rotation of a charge holding object

    DOE Patents [OSTI]

    Gerald, II, Rex E. (Brookfield, IL); Vukovic, Lela (Westchester, IL); Rathke, Jerome W. (Homer Glenn, IL)

    2009-10-13T23:59:59.000Z

    A device and a method for the production of a magnetic field using a Charge Holding Object that is mechanically rotated. In a preferred embodiment, a Charge Holding Object surrounding a sample rotates and subjects the sample to one or more magnetic fields. The one or more magnetic fields are used by NMR Electronics connected to an NMR Conductor positioned within the Charge Holding Object to perform NMR analysis of the sample.

  9. Investigating Cell Adhesion via Parallel Disk Rotational Flow: A Biocompatibility Study

    E-Print Network [OSTI]

    Rocha, Aracely

    2011-08-08T23:59:59.000Z

    INVESTIGATING CELL ADHESION VIA PARALLEL DISK ROTATIONAL FLOW: A BIOCOMPATIBILITY STUDY A Thesis by ARACELY ROCHA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 2008 Major Subject: Mechanical Engineering INVESTIGATING CELL ADHESION VIA PARALLEL DISK ROTATIONAL FLOW: A BIOCOMPATIBILITY STUDY A Thesis by ARACELY ROCHA Submitted to the Office...

  10. Main effects of the Earth's rotation on the stationary states of ultra-cold neutrons

    E-Print Network [OSTI]

    Mayeul Arminjon

    2007-11-13T23:59:59.000Z

    The relativistic corrections in the Hamiltonian for a particle in a uniformly rotating frame are discussed. They are shown to be negligible in the case of ultra-cold neutrons (UCN) in the Earth's gravity. The effect, on the energy levels of UCN, of the main term due to the Earth's rotation, i.e. the angular-momentum term, is calculated. The energy shift is found proportional to the energy level itself.

  11. Spin-rotation contribution to the relaxation time of the fluorine nuclei in benzotrifluoride

    E-Print Network [OSTI]

    Faulk, Robert Hardy

    1965-01-01T23:59:59.000Z

    SPIN-ROTATION CONTRIBUTION TO THE RELAXATION TIME OF THE FLUORINE NUCLEI IN BENZOTRIFLUORIDE A Thesis By ROBERT HARDY FAULK Submitted to the Graduate College of the Texas ASM University in partial fulfillment of the requirements... Contributions to the Relaxation Time for the Fluorine 6 Hydrogen Relaxation Time and the Correlation Time 33 35 36 I. INTRODUCTION The spin-rotation interaction may be visualized in the following manner. Because of the inhomogeneous distribution of charge...

  12. Thomas Rotation and Polarised Light: A non-Abelian Geometric Phase in Optics

    E-Print Network [OSTI]

    Joseph Samuel; Supurna Sinha

    1997-05-13T23:59:59.000Z

    We describe a non-Abelian Berry phase in polarisation optics, suggested by an analogy due to Nityananda between boosts in special relativity and the effect of elliptic dichroism on polarised light. The analogy permits a simple optical realization of the non-Abelian gauge field describing Thomas rotation. We also show how Thomas rotation can be understood geometrically on the Poincar\\'{e} sphere in terms of the Pancharatnam phase.

  13. Calibrating High-Precision Faraday Rotation Measurements for LOFAR and the Next Generation of Low-Frequency Radio Telescopes

    E-Print Network [OSTI]

    Sotomayor-Beltran, C; Hessels, J W T; de Bruyn, G; Noutsos, A; Alexov, A; Anderson, J; Asgekar, A; Avruch, I M; Beck, R; Bell, M E; Bell, M R; Bentum, M J; Bernardi, G; Best, P; Birzan, L; Bonafede, A; Breitling, F; Broderick, J; Brouw, W N; Brueggen, M; Ciardi, B; de Gasperin, F; Dettmar, R -J; van Duin, A; Duscha, S; Eisloeffel, J; Falcke, H; Fallows, R A; Fender, R; Ferrari, C; Frieswijk, W; Garrett, M A; Griessmeier, J; Grit, T; Gunst, A W; Hassall, T E; Heald, G; Hoeft, M; Horneffer, A; Iacobelli, M; Juette, E; Karastergiou, A; Keane, E; Kohler, J; Kramer, M; Kondratiev, V I; Koopmans, L V E; Kuniyoshi, M; Kuper, G; van Leeuwen, J; Maat, P; Macario, G; Markoff, S; McKean, J P; Mulcahy, D D; Munk, H; Orru, E; Paas, H; Pandey-Pommier, M; Pilia, M; Pizzo, R; Polatidis, A G; Reich, W; Roettgering, H; Serylak, M; Sluman, J; Stappers, B W; Tagger, M; Tang, Y; Tasse, C; ter Veen, S; Vermeulen, R; van Weeren, R J; Wijers, R A M J; Wijnholds, S J; Wise, M W; Wucknitz, O; Yatawatta, S; Zarka, P; 10.1051/0004-6361/201220728

    2013-01-01T23:59:59.000Z

    Faraday rotation measurements using the current and next generation of low-frequency radio telescopes will provide a powerful probe of astronomical magnetic fields. However, achieving the full potential of these measurements requires accurate removal of the time-variable ionospheric Faraday rotation contribution. We present ionFR, a code that calculates the amount of ionospheric Faraday rotation for a specific epoch, geographic location, and line-of-sight. ionFR uses a number of publicly available, GPS-derived total electron content maps and the most recent release of the International Geomagnetic Reference Field. We describe applications of this code for the calibration of radio polarimetric observations, and demonstrate the high accuracy of its modeled ionospheric Faraday rotations using LOFAR pulsar observations. These show that we can accurately determine some of the highest-precision pulsar rotation measures ever achieved. Precision rotation measures can be used to monitor rotation measure variations - e...

  14. Analysis of buoyancy and tube rotation relative to the modified chemical vapor deposition process

    SciTech Connect (OSTI)

    Choi, M.; Lin, Y.T.; Greif, R. (Univ. of California, Berkeley (USA))

    1990-11-01T23:59:59.000Z

    The secondary flows resulting from buoyancy effects in respect to the MCVD process have been studied in a rotating horizontal tube using a perturbation analysis. The three-dimensional secondary flow fields have been determined at several axial locations in a tube whose temperature varies in both the axial and circumferential directions for different rotational speeds. For small rotational speeds, buoyancy and axial convection are dominant and the secondary flow patterns are different in the regions near and far from the torch. For moderate rotational speeds, the effects of buoyancy, axial and angular convection are all important in the region far from the torch where there is a spiraling secondary flow. For large rotational speeds, only buoyancy and angular convection effects are important and no spiraling secondary motions occurs far downstream. Compared with thermophoresis, the important role of buoyancy in determining particle trajectories in MCVD is presented. As the rotational speed increases, the importance of the secondary flow decreases and the thermophoretic contribution vecomes more important. It is noted that thermophoresis is considered to be the main cause of particle deposition in the MCVD process.

  15. Tests of the Tully-Fisher Relation II: Scatter Using Optical Rotation Curves

    E-Print Network [OSTI]

    Somak Raychaudhury; Kaspar von Braun; Gary M. Bernstein; Puragra Guhathakurta

    1997-03-26T23:59:59.000Z

    We investigate the amount of scatter in the Tully-Fisher relation (TFR) when using optical long-slit H-alpha rotation curves to determine the velocity widths of spiral galaxies. We study a sample of 25 galaxies in the Coma region of the sky which were shown in Bernstein et al. (1994) to exhibit an extraordinarily low scatter of 0.10 mag RMS in the I magnitude vs 21-cm width TFR. Using the same I magnitudes with new widths derived from high-quality H-alpha rotation curves, we measure an RMS scatter of 0.14 mag in the TFR. This suggests that measurement errors and ``astrophysical errors'' (such as non-circular gas motion) on the H-alpha velocity widths are below 6%, and optical widths are nearly as good for TFR studies as 21-cm widths. The scatter and form of the TFR are found to be robust under choice of velocity width-extraction algorithm, as long as the central portions of the optical rotation curve are ignored and low-S/N points are not weighted too heavily. In this small sample there is no evidence that rotation curve shapes vary systematically with rotation velocity, nor that rotation curve shape can be used to reduce the scatter in the TFR.

  16. Pressure change and transport process on flames formed in a stretched, rotating flow

    SciTech Connect (OSTI)

    Yamamoto, Kazuhiro [Toyohashi Univ. of Technology, Aichi (Japan). Dept. of Mechanical Engineering] [Toyohashi Univ. of Technology, Aichi (Japan). Dept. of Mechanical Engineering

    1999-08-01T23:59:59.000Z

    Flame characteristics in a stretched, rotating flow have been investigated by numerical simulation of tubular laminar flames for lean hydrogen, methane, and propane/air mixtures. Twin planar flames in counterflow have been also simulated for comparison. A fixed inlet velocity at the porous wall of the burner was assumed in all cases, and the cylindrical containing tube (radius R = 9.5 mm) was either maintained stationary or rotated. Results showed that, within the range studied, the flame temperatures always increase monotonically with increasing fuel concentration, and at the same time the reaction zones move outwards. However, while the introduction of rotation also causes a monotonic temperature increase of hydrogen and methane air mixtures, that of a propane/air mixture decreases. The temperature change with rotation becomes smaller with an increase of the fuel concentration. As a consequence of the centrifugal force, {rho}{nu}{sub {theta}}{sup 2}/r, induced by the rotation, a pressure gradient is formed in the cylindrical containing tube, with low pressure along the axis. The pressure gradient at the outer, unburnt edge of the flame reaction zone becomes smaller as the fuel concentration increases. The resultant decreased mass transport by pressure diffusion provides an explanation for part of the above-mentioned temperature change associated with rotation. The remainder of the effect is associated with changed stretch characteristics of the flames.

  17. The lithium-rotation correlation for WTTS in Taurus-Auriga

    E-Print Network [OSTI]

    L. F. Xing; J. R. Shi; J. Y. Wei

    2006-10-30T23:59:59.000Z

    Surface lithium abundance and rotation velocity can serve as powerful and mutually complementary diagnostics of interior structure of stars. So far, the processes responsible for the lithium depletion during pre-main sequence evolution are still poorly understood. We investigate whether a correlation exists between equivalent widths of Li (EW(Li)) and rotation period (P$_{rot}$) for Weak-line T Tauri stars (WTTSs). We find that rapidly rotating stars have lower EW(Li) and the fast burning of Li begins at the phase when star's P$_{rot}$ evolves towards 3 days among 0.9M$_\\odot$ to 1.4M$_\\odot$ WTTSs in Taurus-Auriga. Our results support the conclusion by Piau & Turch-Chi\\'eze about a model for lithium depletion with age of the star and by Bouvier et al. in relation to rotation evolution. The turn over of the curve for the correlation between EW(Li) and P$_{rot}$ is at the phase of Zero-Age Main Sequence (ZAMS). The EW(Li) decreases with decreasing P$_{rot}$ before the star reaches the ZAMS, while it decreases with increasing P$_{rot}$ (decreasing rotation velocity) for young low-mass main sequence stars. This result could be explained as an age effect of Li depletion and the rapid rotation does not inhibit Li destruction among low mass PMS stars.

  18. THE FIRST OBSERVATION OF A RAPIDLY ROTATING CORONAL MASS EJECTION IN THE MIDDLE CORONA

    SciTech Connect (OSTI)

    Vourlidas, A.; Colaninno, R. [Solar Physics Branch, Space Sciences Division, Naval Research Laboratory, Washington, DC (United States); Nieves-Chinchilla, T. [Department of Physics, Catholic University of America, Washington, DC (United States); Stenborg, G. [Interferometrics, Inc., Herdon, VA (United States)

    2011-06-01T23:59:59.000Z

    In this Letter, we present the first direct detection of a rotating coronal mass ejection (CME) in the middle corona (5-15 R{sub sun}). The CME rotation rate is 60{sup 0} day{sup -1}, which is the highest rate reported yet. The Earth-directed event was observed by the STEREO/SECCHI and SOHO/LASCO instruments. We are able to derive the three-dimensional morphology and orientation of the CME flux rope by applying a forward-fitting model to simultaneous observations from three vantage points (SECCHI-A, -B, LASCO). Surprisingly, we find that even such rapidly rotating CME does not result in significant projection effects (variable angular width) in any single coronagraph view. This finding may explain the prevalent view of constant angular width for CMEs above 5 R{sub sun} and the lack of detections of rotating CMEs in the past. Finally, the CME is a 'stealth' CME with very weak low corona signatures as viewed from Earth. It originated from a quiet-Sun neutral line. We tentatively attribute the fast rotation to a possible disconnection of one of the CME footpoints early in the eruption. We discuss the implications of such rotations to space weather prediction.

  19. Rotating electrical machines - Part 15: Impulse voltage withstand levels of rotating a.c. machines with form-wound stator coils

    E-Print Network [OSTI]

    International Electrotechnical Commission. Geneva

    1995-01-01T23:59:59.000Z

    Applies to rotating a.c. machines for rated voltages from 3 kV to 15 kV inclusive and incorporating form-wound stator coils. Specifies the rated phase-to-earth impulse voltage withstand levels and the test procedure and voltages to be applied to the main and interturn insulation of sample coils.

  20. Rotation speed and stellar axis inclination from p modes: How CoRoT would see other suns

    E-Print Network [OSTI]

    J. Ballot; R. A. Garcia; P. Lambert

    2006-03-24T23:59:59.000Z

    In the context of future space-based asteroseismic missions, we have studied the problem of extracting the rotation speed and the rotation-axis inclination of solar-like stars from the expected data. We have focused on slow rotators (at most twice solar rotation speed), firstly because they constitute the most difficult case and secondly because some of the CoRoT main targets are expected to have slow rotation rates. Our study of the likelihood function has shown a correlation between the estimates of inclination of the rotation axis i and the rotational splitting deltanu of the star. By using the parameters, i and deltanu*=deltanu sin(i), we propose and discuss new fitting strategies. Monte Carlo simulations have shown that we can extract a mean splitting and the rotation-axis inclination down to solar rotation rates. However, at the solar rotation rate we are not able to correctly recover the angle i although we are still able to measure a correct deltanu* with a dispersion less than 40 nHz.