I review the X-ray observations of galactic accreting black holes and neutron stars and interpretations of these in terms of solutions of the accretion flow equations. PMID:12804240

Possible mechanisms for the formation of the planets, natural satellites, and asteroids in the solar

... Accession Number : ADP001669. Title : Mechanisms for Ice Bonding in Wet Snow Accretions on Power Lines,. Corporate ...

X-ray timing of the accretion-powered pulsations during the 2003 outburst of the accreting millisecond pulsar XTE J1814-338 has revealed variation in the pulse time of arrival residuals. These can be interpreted in several ways, including spin-down and wandering of the fuel impact point around the magnetic pole. In this Letter we show ...

The Lyman edge region in the spectra of 11 high-redshift quasars is studied using data designed to detect broadened Lyman edge absorption predicted by thermal models of the 'big blue bump' continuum component, especially thin accretion disks. Three objects have broadened, partial edges near the systemic redshifts, as expected for thermal models. In two cases, ...

This grant supported our ongoing project to characterize the accretion rate of interplanetary dust particles (IDPs) to Earth over geologic time using He-3 as a tracer. IDPs are derived from collisions in the asteroid belt and from disaggregation of active comets. Owing to their small size (few to few hundred micrometers diameter) these particles spiral into the sun under ...

The influence of accretion disk instabilities on the UV fluxes of Seyfert 1 galaxies was studied. The observed characteristic timescales of variability are consistent with the interpretation that most of the UV radiation originates in an accretion disk, a...

It is proposed a new mechanism for high energy gamma ray burst in Supernova type I (SNI) explosion. Presupernova is assumed to be a binary system comprised of a red giant and a white dwarf with a wind accretion. The accretion flow terminates by the accret...

We performed a systematic analysis of all INTEGRAL observations from 2003 to 2009 of 14 supergiant fast X-ray transients (SFXTs), implying a net exposure time of about 30 Ms. For each source we obtained light curves and spectra (3-100 keV), discovering several new outbursts. We discuss the X-ray behaviour of SFXTs emerging from our analysis in the framework of the clumpy wind ...

We present seven separate Chandra observations of the 2001 superoutburst of WZ Sge. The high-energy outburst was dominated by intense EUV emission lines, which we interpret as boundary layer emission scattered into our line of sight in an accretion disc wind. The direct boundary layer emission was hidden from view, presumably by the ...

The growth of supermassive black holes (BHs) located at the centers of their host galaxies comes mainly from accretion of gas, but how to fuel them remains an outstanding unsolved problem in quasar evolution. This issue can be elucidated by quantifying the radiative efficiency parameter ($\\eta$) as a function of redshift, which also provides constraints on the average spin of ...

A possible interpretation of the strong Fe-K line is the line-photon beaming in the WD accretion column, due to resonance scattering of line photons ...

The accretion during condensation mechanism is used to explain the differences in composition of the

The status of work concerned with understanding the angular momentum transport mechanisms as applied

Neutron viscosity is investigated as a possible mechanism for the dissipation of kinetic energy into

The core accretion mechanism of giant planet formation has been used to explain ... system earth and planetary science letters earth and planetary science ...

Jan 22, 2011 ... Title: The Production of Jets From Magnetized Accretion Disks: Simulation of the Blandford-Payne Mechanism. Authors: Meier, D. ...

Jan 22, 2011 ... Title: The Production of Jets From Magnetic Accretion Disks: Simulation of the Blandford-Payne Mechanism. Authors: Meier, David L. ...

Accretion disks are invoked to explain a host of astrophysical phenomena, from protostellar objects to AGN. And yet the mechanism allowing accretion disks to operate are completely unknown. This proposal seeks to observe the ``smoking gun'' signature of magnetically-driven viscosity in accretion disks. ...

It is known that certain problems in partial differential equations may be interpreted as initial value problems for ordinary differential equations in Banach spaces. When such an evolution equation is governed by an accretive operator, then its solutions...

... AD0612488. Title : STRUCTURAL INTERPRETATIONS OF MECHANICAL PROPERTIES OF POLYCRYSTALLINE POLYMERS,. ...

An approximation theory of the acceleration of particles in low-density shear flows is developed and is applied to a number of astrophysical flows including accretion disks, radial accretion, and convective turbulence. In the disk application, the theory suggests a mechanism by which the bulk of the accretion power ...

T Tauri stars (TTS) are low-mass pre-main-sequence stars that are accreting mass from the surrounding disc. The hotspots detected in some of them are probably heated by the release of gravitational energy in the accretion of the disc material on to the star. In this work we study the UV spectrum of the hotspot detected in DI Cep to constrain the physical ...

thermonuclear flashes on accreting neutron stars are compared. ... An ignition mechanism of the bursts is proposed in terms of elemental mixing and ...

Mar 1, 2011 ... thermonuclear flashes on accreting neutron stars are compared. ... An ignition mechanism of the bursts is proposed in terms of elemental ...

The 2006 outburst of GK Persei differed significantly at optical and ultraviolet (UV ) ... liberated during accretion, and interpret the optical/UV outburst profile as ...

... blastogenetic stages with the earliest corallite having one axial initial septum. To interpret the phylogenetic status of ... oblique to the mid-septal zone, indicating predominant axial accretion of the ...

The inverse problem of interpreting the SS 433 optical light curves is solved for a geometrically thick model accretion disk around the compact relativistic object: most likely a black hole.

The self-sustained turbulence that develops in magnetized accretion disks is suppressed in the weakly ionized, quiescent disks of close binary stars. Because accretion still proceeds during quiescence, another viscosity mechanism operates in these systems. An anticorrelation of the recurrence times of SU UMa dwarf novae with their mass ...

The authors examine the possibility of neutron viscosity as the mechanism responsible for the dissipation of kinetic energy into luminosity in the innermost parts (r < 100 R sub s) of accretion disks surrounding compact objects. They present simplified models of such self-consistent, steady state accretion flows in which the ...

We review recent results from the X-ray timing of accreting millisecond pulsars in LMXBs. This is the first time a timing analysis is performed on accreting millisecond pulsars, and for the first time we can obtain information on the behavior of a very fast pulsar subject to accretion torques. We find both spin-up and spin-down ...

We review recent results from the X-ray timing of accreting millisecond pulsars in LMXBs. This is the first time a timing analysis is performed on accreting millisecond pulsars, and for the first time we can obtain information on the behavior of a very fast pulsar subject to accretion torques. We find both spin-up and spin-down ...

An explanation of the magnetic fields of the universe, the central mass concentration of galaxies, the massive black hole of every galaxy, and the AGN phenomena has been an elusive goal. We suggest here the outlines of such a theoretical understanding and point out where the physical understanding is missing. We believe there is an imperative to the sequence of mass flow and hence energy flow in ...

A method is proposed for restoring the structure of the accretion disk in a binary system from analysis of eclipse curves. Application of the method to the x-ray binary HZ Herculis yields the distribution of brightness and color temperatures over the optical accretion disk associated with the neutron star. The luminosity, mean temperature, and size of the ...

Many accreting neutron stars do so intermittently; that is, the accretion ceases for long quiescent intervals. During the accretion outburst, reactions are induced in the crust by the continual accumulation of matter. These reactions heat the crust out of thermal equilibrium with the core, and when accretion stops ...

Many accreting neutron stars do so intermittently; that is, the accretion ceases for long quiescent intervals. During the accretion outburst, reactions are induced in the crust by the continual accumulation of matter. These reactions heat the crust out of thermal equilibrium with the core, and when accretion stops ...

The broadened iron lines observed from accreting compact objects are most easily interpreted in terms of reflection onto the accretion disc of the hard X-ray photons emitted by the central source. In this context, such a broadness is due to the relativistic motion of the reflecting plasma, in the deep gravitational well of the compact ...

It is shown that the de-excitation of convection elements in accretion disks considerably reduces convective energy transfer. The energy transferred by floating-up magnetic field tubes is also small. Therefore, radiative transfer is the main mechanism of energy transfer. It is concluded that hot coronae cannot exist around accretion ...

Accretion is a pervasive process in astrophysics. Through accretion, protostars gather enough mass to initiate fusion, and small bodies gather enough mass to become planets. Accretion onto black holes is the second most efficient physical process presently known, allowing up to 30% of the rest-mass energy of the ...

The thermal emission of accretion disks in Active Galactic Nuclei (AGN) is examined. Medium broadband AGN spectra are shown in order to explain the emission mechanism proposed. Basic behaviors from radiation theory and from hydrodynamics of importance for...

THE PRODUCTION OF JETS FROM MAGNETIC ACCRETION DISKS: SIMUI,ATION OF THE BLANDFORD-PAYNE MECHANISM. D. L. Meier, D. G. Payne, K. R. Lind ...

... TITLE: Enhancing Bone Accretion Using Short Duration, Low-Level Mechanical Vibrations ... Bone volume fraction (BV·TV -1 ), trabecular ...

The viscous model for accretion disks encounters difficulties both in providing a source of viscosity and in removing angular momentum from the disk outer edges where it is transported by the viscous stress. This paper investigates radiative tides as an alternative mechanism for accretion in disks in mass-transfer binary systems. We ...

Supercomputer simulations have been used in conjunction with analytic studies to investigate the central issue of astrophysical accretion-disk dynamics: the nature of the angular momentum transport. Simulations provide the means to investigate and experiment with candidate mechanisms, including global hydrodynamic instabilities, spiral shock waves, and ...

We investigate the idea that a sizable fraction of the interferometrically unresolved infrared emission of the nucleus of NGC 1068 might originate from processes other than thermal dust emission from the torus. We examine the contribution of free-free or synchrotron emission to the central mid- and near-IR parsec-scale emitting region of NGC 1068. Each mechanism is constrained ...

This is the second of a series of papers aimed to look for an explanation on the generation of high frequency quasi-periodic oscillations (QPOs) in accretion disks around neutron star, black hole, and white dwarf binaries. The model is inspired by the general idea of a resonance mechanism in the accretion disk oscillations as was ...

Although the powering mechanism for quasars is now widely recognized to be the accretion of matter in a geometrically thin disk, the transport of matter to the inner region of the disk where luminosity is emitted remains an unsolved question. Miralda-Escud� & Kollmeier (2005) proposed a model whereby quasars are fuelled when stars are captured by the ...

Accretion disks are invoked to explain a host of astrophysical phenomena, from protostellar objects to AGN. And yet the mechanism allowing accretion disks to operate are completely unknown. This proposal seeks to observe the smoking gun signature of magnetically--driven viscosity in accretion disks. ...

A magnetodynamic model proposed and worked on by Uchida and collaborators for the star formation jets (bipolar flows), by taking a genetic point of view into account, is reviewed. A large scale magnetic field, which is week in the primordial gas but intensified in the gravitational contraction of the gas, assists the continuous accretion of the gas to the central gravitator by ...

Production of both the large scale CO bipolar flows and the small scale optical bipolar jets from the star-forming regions is given interpretation in terms of a magnetic mechanism related to accretion model. It is shown by an axisymmetric 2.5-dimensional simulation that the large scale cold bipolar flow may be produced in the ...

We review recent results of our group on X-ray timing of accreting millisecond pulsars in LMXBs. The good quality of the RXTE data allow us to obtain information on the behavior of a very fast pulsar subject to accretion torques. We find both spin-up and spin-down behaviors, from which, using available models for the accretion torques, ...

A general mechanism is presented for generating pressure-driven winds that are intrinsically bipolar from objects undergoing disk accretion. The energy librated in a boundary layer shock as the disk matter impacts the central object is shown to be sufficient to eject a fraction ..beta..approx.10/sup -2/ to 10/sup -3/ of the accreted ...

Millisecond pulsars, both during and after accretion, stand a class apart from the general pulsar population due to the much weaker field strength at their surface. The prevailing view is that accretion of matter on to a neutron star causes a decay of its magnetic field strength, as viewed by an external observer. In this paper we review some of the ...

The MOdified Newtonian Dynamics (MOND) is an alternative to the dark matter assumption that can explain the observed flat rotation curve of galaxies. Here hydrodynamic accretion is considered to critically check the consistency and to constrain the physical interpretation of this theory. It is found that, in case of spherically symmetrical hydrodynamic ...

In a massive-star formation process, a high-mass accretion rate is considered to be needed to overcome the strong radiation pressure at the dust sublimation front. We examined the accretion structure near the dust sublimation front and found a new mechanism to overcome this radiation pressure. The weight of the accumulated mass in a ...

The exchange of angular momentum between accreting matter and the magnetosphere of a neutron star is studied as a possible explanation for the soft X-ray emission of X-ray pulsars. The flux of soft X-radiation from Her X-1 may be related to dissipation of rotational energy of accreting matter into a layer of the disk at the radial distance where the ...

The nature of linear perturbations to a thin, shearing accretion disk composed of compressible material is reexamined. Modes that can carry angular momentum throughout the disk are identified, and it is shown how the subsequent dissipation of these waves through nonlinear processes can form the basis of a viscosity mechanism for realistic ...

Based on a series of data collected by Cassini-Huygens, we constrain the composition of the primordial bricks that formed Titan and quantify the chemical exchanges that occurred on Titan between the interior and the atmosphere since its accretion. Assuming that the bricks that formed Titan had a composition close to that of Enceladus and that of the planetesimals in the ...

Aug 1, 1986 ... those of models of thermonuclear flashes on accreting neutron stars are ... An ignition mechanism of the bursts is proposed in terms of ...

Icing; Swept wings; Ice scallop formations; Lobster tails; Cross flow vortices; Cross flow instability; Swept wing ice accretions. NUMBER OF PAGES: ...

Within the framework of unsaturated Compton disk accretion onto a supermassive black hole as a model

We perform computations using a time-dependent model for the accretion disk limit-cycle mechanism to

... in the tibial epiphysis and thicker ... resorption and enhancing bone morphology - effects ... FRACTURE(MECHANICS), *BONES, STRESSES, PEAK ...

separation mechanism is probably more likely for moderate to high-Reynolds number flows. So the bursting of the laminar separation bubble is not a necessary ...

The understanding of accretion processes and in particular of massive accretion disks is one of the most important topics in high-mass star formation. Based on our successful ATCA disk studies of high mass star formation, we now propose to investigate higher J inversion transitions of NH3 at high angular resolution (~1'') to complement our NH3 (4,4) and ...

By combining the numerical solution of the nonlinear hydrodynamics equations with the solution of the linear inhomogeneous Zerilli-Moncrief and Regge-Wheeler equations, we investigate the properties of the gravitational radiation emitted during the axisymmetric accretion of matter onto a Schwarzschild black hole. The matter models considered include quadrupolar dust shells and ...

We have found that two members of the TW Hydrae association, TW Hydrae and Hen 3-600A, are still actively accreting, based on the ballistic infall signature of their broad Halpha emission profiles. We present the first quantitative analysis of accretion in these objects and conclude that the same accretion ...

... Title : REMARKS ON THE QUANTUM MECHANICAL INTERPRETATION OF THE STARK EFFECT IN THE HYDROGEN ATOM. ...

Within the framework of the main problem of cosmogony related to the reconstruction of the evolution of the protoplanetary gas-dust cloud that surrounded the proto-Sun at an early stage of its existence, we have derived a closed system of magnetohydrodynamic equations for the scale of mean motion in the approximation of single-fluid magnetohydrodynamics designed to model the shear and convective ...

Quantum mechanical operators are interpreted according to their equations of motion. A gauge invariant interpretation of quantum mechanics is obtained by expanding the wave function (in an arbitrary gauge) in the orthonormal set of eigenfunctions of the p...

In this study, the mechanics of forearc basins will be the object of a numerical investigation to understand the relationships between wedge deformation and forearc basin formation. The aim of this work is to gain an insight into the dynamics of the formation of the forearc basin, in particular the mechanism of formation of accommodation space and the ...

The MOdified Newtonian Dynamics (MOND) is one alternative to the dark matter assumption that can explain the observed flat rotation curve of galaxies. Here, spherically symmetrical hydrodynamic accretion in MOND regime is considered to critically check the consistency, and to constrain the physical interpretation of this theory. The modified Euler's ...

Some aspects of hot spots or giant flares on supermassive accretion disks are investigated, with particular emphasis on the circumstances under which the orbital motion of such a spot can lead to a quasi-linear rate of rotation of the polarization position angle. A tentative interpretation of recent polarization observations of AO 0235+164 is given, and ...

The environments of both hot and cool stars are the sites of highly dynamic processes involving motion of gas and plasma in winds, flows across shocks, plasma motions in closed magnetic fields, or streams along magnetospheric accretion funnels. X-ray spectroscopy has opened new windows toward the study of these processes. Kinematics are evident in line shifts and line ...

I have used spectropolarimetric observations combined with three-dimensional Monte Carlo radiative transfer models to investigate the geometrical and optical characteristics of circumstellar material in binary- accretion disk systems. Knowledge of these characteristics can provide important clues to the mechanism that drives the mass loss from the binary ...

We investigate the role of the compact object in the production of jets from neutron star X-ray binaries. The goal is to quantify the effect of the neutron star spin, if any, in powering the jet. We compile all the available measures or estimates of the neutron star spin frequency in jet-detected neutron star X-ray binaries. We use as an estimate of the ranking jet power for each source, the ...

Extrasolar planet surveys have begun to detect planets in orbit around M dwarf stars. The frequency of gas giant planets around M dwarfs appears to be lower than that around G dwarfs, but it is not zero. Core accretion is too slow to form gas giant planets around M dwarfs. Disk instability is fast enough to form gas giant protoplanets around low mass stars well before the ...

We describe a Newtonian version of the theory of thick accretion disks orbiting black holes. In view of the present inadequate knowledge of microscopic viscosity process, this theory adopts a macroscopic approach. All the uncertainties are absorbed in currently arbitrary functions lambda(xi) and f(xi) which describe the (non-Keplerian) angular momentum along the disk, and the ...

Neutron viscosity is investigated as a possible mechanism for the dissipation of kinetic energy into luminosity in the innermost parts of accretion disks around compact objects. Simplified models are presented of the self-consistent, steady-state accretion flows in which viscosity is provided by neutron collisions with ...

OAK-B135 We consider an accretion flow model originally proposed by Bisnovatyi-Kogan and Ruzmaikin (1974), which has been confirmed in recent 3D MHD simulations. In this model, the accreting gas drags in a strong poloidal magnetic field to the center such that the accumulated field disrupts the axisymmetric accretion flow at a ...

Young stars can produce X-rays by different mechanisms: Coronal activity, accretion shocks and shocks in outflows. We propose to observe two targets within one field-of-view (FOV): SU Aur is accreting mass from a disk and shows violent coronal activity. We will study the time evolution of stellar flares on time scales from seconds to ...

This paper studies the production of high-energy gamma radiation (E-gamma about 100 MeV) in the vicinity of a black hole through the collisions of accreting protons on the stable orbits. A spherical accretion with a small rate is considered as a fully computable example. If the accretion rate is about 0.001 of the critical rate, ...

Five AM Herculis binary systems show an optical QPO that is known to be associated with magentically channeled polar cap accretion. Hard X-ray QPOs are predicted by the time-depndent hydrodynamic models. We propose to search selected AM Her systems for polar cap X-ray QPOs using the XTE PCA. Because of its large collecting area, the PCA is the only instrument that can do this ...

., 1986). Other profiles across the British Caledonides have been interpreted as showing fragmented). The Caledonide orogen is a sequence of tectonostratigraphic terranes accreted to the margin of the Lewisian and the Lake District, possibly of oceanic or of island arc affinity. South of the main Caledonide structures

Mar 1, 2011 ... Considerable interest exists in the accretion rate for condensates in nonequilibrium flow with icing ... from crossed light beam correlations and electric probes. ... interpreted using a boundary layer model of contact surface flow ... instability is probably responsible for the observed phenomenon. ...

We present seven separate Chandra observations of the 2001 superoutburst of WZ Sge. The high-energy outburst was dominated by intense EUV emission lines, which we interpret as boundary layer emission scattered into our line of sight in an accretion disc w...

By careful measurements of the fluctuations in pulsar pulse periods on time scales of days and longer, researchers determined that these fluctuations are caused by changes in the rotation rate of the stellar crust apparently arising from matter accretion....

We received Type A and B funding under the NASA Astrophysics Data Program for the analysis and interpretation of hard x-ray data obtained by the Rossi X-ray Timing Explorer and other NASA sponsored missions for Intermediate Polars (IPS) and Polars. For so...

About half of the binary systems are close enough to each other for mass to be exchanged between them at some point in their evolution, yet the accretion mechanism in wind accreting binaries is not well understood. We study the dynamical effects of gravitational focusing by a binary companion on winds from late-type stars. In ...

... Title : Interpretation of Toughness in Aromatic Polymer Composites Using a Fracture Mechanics Approach,. Corporate Author : ...

... Accession Number : ADD444096. Title : Acid-Base Interactions in the Interpretation of Aramid Composite and Fabric Mechanics,. ...

The warped spacetime near black holes is one of the most exotic observable environments in the Universe. X-ray spectra from active galaxies obtained with the current generation of X-ray observatories reveal line emission that is modified by both special relativistic and general relativistic effects. The interpretation is that we are witnessing X-ray irradiated matter orbiting ...

The mass assembly of galaxies leaves various imprints on their surroundings, such as shells, streams and tidal tails. The frequency and properties of these fine structures depend on the mechanism driving the mass assembly: e.g. a monolithic collapse, rapid cold-gas accretion followed by violent disk instabilities, minor mergers or major dry / wet mergers. ...

The latest outburst of the recurrent nova RS Oph occurred in 2006 February. Photometric data presented here show evidence of the resumption of optical flickering, indicating re-establishment of accretion by day 241 of the outburst. Magnitude variations of up to 0.32mag in V band and 0.14mag in B band on time-scales of 600-7000s are detected. Over the two-week observational ...

The latest outburst of the recurrent nova RS Oph occurred in 2006 February. Photometric data presented here show evidence of the resumption of optical flickering, indicating re-establishment of accretion by day 241 of the outburst. Magnitude variations of up to 0.32 mag in the V-band and 0.14 mag in B on time-scales of 600-7000 s are detected. Over the two week ...

Galactic nuclei should contain a cluster of stars and compact objects in the vicinity of the central supermassive black hole due to stellar evolution, minor mergers and gravitational dynamical friction. By analogy with protoplanetary migration, nuclear cluster objects (NCOs) can migrate in the accretion discs that power active galactic nuclei (AGN) by exchanging angular ...

Analysis of thick, radiation pressure dominated (super-Eddington) accretion disks has proven to be difficult. Purely analytical methods have not yet been adequate to determine the structure of the disk and associated jet. The work presented here circumvents the analytical problems by using a numerical method; the results are based on a series of numerical simulations of disk ...

In massive star formation (gsim 40 M sun) by core accretion, the direct stellar radiation pressure acting on the dust particles exceeds the gravitational force and interferes with mass accretion at the dust sublimation front, the first absorption site. Ram pressure generated by high accretion rates of 10-3 M sun yr-1 is thought to be ...

The illumination of companion stars in very low mass X-ray binaries by various kinds of radiation from the neighborhood of the neutron star after accretion has terminated or during accretion is considered. If a neutron star's spun-up period approaches 0.001 s, pulsar kHz radiation can quench accretion by pushing surrounding ...

During the formation of a massive star, strong radiation pressure from the central star acts on the dust sublimation front and tends to halt the accretion flow. To overcome this strong radiation pressure, it has been considered that a strong ram pressure produced by a high-mass accretion rate of 10-3 M sun yr-1 or more is needed. We reinvestigated the ...

During the formation of a massive star, strong radiation pressure from the central star acts on the dust sublimation front and tends to halt the accretion flow. To overcome this strong radiation pressure, it has been considered that a strong ram pressure produced by a high-mass accretion rate of 10{sup -3} M{sub sun} yr{sup -1} or more is needed. We ...

The report is a theoretical and experimental study of ways to use context for automatic interpretation of aerial photography. One type of photo interpretation system interprets a frame of aerial photography by dividing the frame into several square cells ...

There are two dominant models of how stars form. Under gravitational collapse, star-forming molecular clumps, of typically hundreds to thousands of solar masses (M(o)), fragment into gaseous cores that subsequently collapse to make individual stars or small multiple systems. In contrast, competitive accretion theory suggests that at birth all stars are much smaller than the ...

Three interpretations of quantum mechanics are reexamined: the orthodox or ''Copenhagen'' interpretation, the expanding worlds interpretation and the interpretation that is generally named statistical. It is concluded that the first two ...

Context. The number of strong iron K? line detections in Seyfert AGN is clearly growing in the Chandra, XMM-Newton and Suzaku era. The iron emission lines are broad, some are relativistically blurred. These relativistic disk lines have also been observed for galactic black hole X-ray binaries. Thermal components found in hard spectra were interpreted as an indication for a ...

Theoretical models of cosmic gamma bursts fall into four categories: extra galactic models, flares, accretion onto collapsed stars, and exotic mechanisms. Factors such as source properties, source dimensions, and radiation mechanisms are considered, in discussing these models. 36 references. (BJG)

This book contains papers presented at a conference on arctic and polar technology. The topics covered are: Ice properties; Ice mechanics and dynamics; Spray ice technology; Ice forces; Ice accretion; Standards on arctic developments; The Barents Sea; and Arctic structures and drilling.

Reduced rates of skeletal muscle accretion are a prominent feature of the metabolic response to sepsis in infants and children. Septic neonates often require medical support with mechanical ventilation (MV). The combined effects of MV and sepsis in muscle have not been examined in neonates, in whom ...

A dark-matter-only Horizon Project simulation is used to investigate the environment and redshift dependences of accretion on to both haloes and subhaloes. These objects grow in the simulation via mergers and via accretion of diffuse non-halo material, and we measure the combined signal from these two modes of accretion. It is found ...

The rotation period of classical T Tauri stars (CTTS) represents a longstanding puzzle. While young low-mass stars show a wide range of rotation periods, many CTTS are slow rotators, spinning at a small fraction of breakup, and their rotation period does not seem to shorten, despite the fact that they are actively accreting and contracting. Matt & Pudritz proposed that the ...

Resistivity and bulk-density logs acquired while drilling are used to document the evolution of porosity, volumetric loss, and effective stress in the upper 300 m of the Barbados accretionary prism. The computed profiles across a thrust fault enable the separation of pre-, syn-, and post-accretion components; total volume loss is divided into normal consolidation ...

We consider the specific case of disc accretion for negligibly low viscosity and infinitely high electric conductivity. The key component in this model is the outflowing magnetized wind from the accretion disc, since this wind effectively carries away angular momentum of the accreting matter. Assuming magnetic field has variable ...

Quantum mechanical operators are interpreted according to their equations of motion. A gauge invariant interpretation of quantum mechanics is obtained by expanding the wave function (in an arbitrary gauge) in the orthonormal set of eigenfunctions of the particle's energy operator (in the same ...

A dispersion relation for linearized perturbation of a geometrically thin accretion disk is derived for an arbitrary viscosity law and cooling mechanism. Using this equation, we formulate the necessary and sufficient conditions for the stability of a disk. The conditions which are imposed on the viscosity and the cooling process are general and can be used ...

The polytropic relation between pressure and density of wind gases is used to obtain solutions for optically thin hot accretion disks with winds. It is assumed that the cooling mechanisms in the disks are bremsstrahlung and Compton scattering. This extends the previous work of Takahara et al. (1989) which did not analyze winds within a self-consistent disk ...

The short-period Algol system TZ Eri was observed spectroscopically during 10 eclipses in order to study the accretion disk surrounding the primary star. It is shown that this disk belongs to the class of transient accretion disks which are produced by a collision of the gas stream with the mass-gaining star. Even without known system parameters, it can be ...

An approximate analytic theory of a thick accretion disk is used to derive the thermodynamic conditions which prevail inside the disk as a function of the black hole mass, the viscosity parameter, and the accretion rate. From these thermodynamic conditions it is shown that, for a given mechanism for viscosity, the nuclear burning is ...

We have constructed vertically integrated, steady state convective models of accretion disks to explore the mechanism of instability in dwarf novae. The models and observations of dwarf novae suggest a picture in which transferred matter piles up in an optically thin torus. The torus eventually becomes optically thick and the resulting convective structure ...

Vertically integrated, steady state convective models of accretion disks have been constructed to explore the mechanism of instability in dwarf novae. The models and observations of dwarf novae suggest a picture in which transferred matter piles up in an optically thin torus. The torus eventually becomes optically thick, and the resulting convective ...

In this paper I review Tony Sudberys foundational work with a view to tracing the evolution of his ideas about the measurement problem and the interpretation of quantum mechanics.

A new point of view on the interpretation of quantum mechanics previously presented is extended. The results are generalized for the case of the presence of an electromagnetic field. (T.R.H.)

Mechanisms of crustal accretion at mid-ocean ridges depend upon the balance between the rate of magma supply and the rate of cooling. The former can be estimated if integrated over long time intervals but the episodicity is very unclear. The latter depends principally on the efficiency of hydrothermal cooling which is poorly constrained. The cooling rate ...

The terrestrial planets are believed to have formed by accretion from an initially cold and chemically homogeneous cloud of dust and gas. The iron occurring in the dust particles of the cloud was present in a completely oxidised form. Either before or during accretion of dust into planets, partial reduction of oxidised iron to metal occurred. The role of ...

Accretion describes the process by which matter in an astrophysical disk falls onto a central massive object. Accretion disks are present in many astrophysical situations including binary star systems, young stellar objects, and near black holes at the center of galaxies. Measurements from observations of these disks have shown that viscous processes are ...

Stochastic events may lead to accretion in Saturn's rings Larry W. Esposito LASP, University of Colorado UVIS occultations indicate accretion is triggered at the B ring edge, in strong density waves in ring A and in the F ring. Moons may trigger accretion by streamline crowding (Lewis & Stewart); which enhances collisions, leading ...

Here we present a self-consistent, bimodal stationary solution for spherically symmetric flows driven by young massive stellar clusters with a central supermassive black hole (SMBH). We demonstrate that the hydrodynamic regime of the flow depends on the location of the cluster in the 3D (star cluster mechanical luminosity-BH mass-star cluster radius) parameter space. We show ...

The energy associated with the accretion of the earth and the segregation of the core is more than sufficient to melt the entire earth. In order to understand the thermal evolution of the early earth it is necessary to study the relevant heat transfer mechanisms. In this paper we postulate the existence of a global magma ocean and carry out calculations of ...

N-body experiments on an accretion disk comprised of weakly self-gravitating particles in a background Keplerian potential are described. The results show that spiral waves are an important mechanism for the accretion of particles in a rotating disk via angular momentum losses. The spiral waves give a viscosity to the disk that ...

The exchange of angular momentum between accreting matter and the magnetosphere of a neutron star is studied as a possible explanation for the soft X-ray emission of X-ray pulsars. The flux of soft X-radiation from Her X-1 may be related to dissipation of rotational energy of accreting matter into a layer of the disk at the radial distance where the ...

Accretion onto compact objects plays a central role in high energy astrophysics. In these environments, both general relativistic and plasma effects may have significant impacts upon the spectral and polarimetric properties of the accretion flow. In paper I we presented a fully general relativistic magnetoionic theory, capable of tracing rays in the ...

We study the effect of radiation pressure on the dust in the inner rim of transitional disks with large inner holes. In particular, we evaluate whether radiation pressure can be responsible for keeping the inner holes dust-free, while allowing gas accretion to proceed. This has been proposed in a paper by Chiang & Murray-Clay (2007, Nature Phys., 3, 604) who explain the ...

The most massive stars can form via standard disk accretion�despite the radiation pressure generated�due to the fact that the massive accretion disk yields a strong anisotropy in the radiation field, releasing most of the radiation pressure perpendicular to the disk accretion flow. Here, we analyze the self-gravity of the forming ...

Many researchers have proposed that the Type I supernova (SNI) explosion originates in a white dwarf (WD) star that is undergoing mass accretion from a companion star in a close binary orbit. Previous hydrodynamic computations by others have described the final result given the WD mass and composition (usually assumed uniform), the mass accretion rate, and ...

We compare accretion and black hole spin as potential energy sources for outbursts from active galactic nuclei (AGNs) in brightest cluster galaxies (BCGs). Based on our adopted spin model, we find that the distribution of AGN power estimated from X-ray cavities is consistent with a broad range of both spin parameters and accretion rates. Sufficient ...

Black holes pose a serious problem in cyclic or oscillating cosmology. It is speculated that, in the cyclic universe with phantom turnarounds, black holes will be torn apart by phantom energy prior to turnaround before they can create any problems. In this paper, using the mechanism of phantom accretion onto black holes, we find that black holes do not ...

Shock degassing was a major factor in releasing the gases present in planetesimals while the earth was in its accretion phase. The atmosphere was formed as the earth grew, and it was of the oxidizing type. As much as 30--45% may have been contributed on the earth by shock degassing, and no less than 25--40% on Venus, but shock degassing played no appreciable role on Mars and ...

the disk --- either entering the jet directly (the #12; BLR Accretion Disk ECC RSy ECD SSC e e + Sy FIGURE 1. Illustration of the model geometry and the relevant fl radiation mechanisms for leptonic jet models. ECD is the height of the blob above the accretion disk. The ECD spectrum can exhibit a strong spectral break

Planet formation in highly inclined binaries is a complex issue. The Kozai mechanism plays an important role in this situation, since it will lead to high eccentricity and high relative impact velocity of planetesimals, thus hinder the planetesimal accretion. However, as we will show here, the presence of gas disk in some circumstance will suppress the ...

Accretion from a disk onto a collapsed, relativistic star--a neutron star or black hole--is the mechanism widely believed to be responsible for the emission from compact X-ray binaries. Because of the extreme spatial resolution required, is not yet possib...

Convection driven by the turbulence of a thin accretion disk could play an important role in the disk structure and stability. A new high-surface-density state of the inner X-ray disk that is secularly stable is discovered when a certain parameter ..beta.. characterizing convective transport exceeds the viscosity parameter ..cap alpha... A bursting ...

in a mixed quantum-classical simulation is provided using the Bohmian interpretation of quantum mechanics- reaction problem based on the de Broglie�Bohm or hy- drodynamic interpretation of quantum mechanics [39 quantum-classical case. Similar to classical mechanics, Bohmian quantum ...

Sensitive high-resolution ion microprobe (SHRIMP) U-Pb dating, laser-ablation multi-collector ICPMS Hf isotope and electron microprobe element analyses of inherited/antecrystal and magmatic zircons from five granitoid intrusions of Linxi area, in the southern segment of the Great Xing�an Range of China were integrated to solve continental crustal growth mechanisms. These ...

We study the spin dependence of accretion onto rotating Kerr black holes using analytic techniques. In its linear regime, angular momentum transport in MHD turbulent accretion flow involves the generation of radial magnetic field connecting plasma in a differentially rotating flow. We take a first principles approach, highlighting the constraint that ...

We study the spin dependence of accretion onto rotating Kerr black holes using analytic techniques. In its linear regime, angular momentum transport in MHD turbulent accretion flow involves the generation of radial magnetic field connecting plasma in a differentially rotating flow. We take a first principles approach, highlighting the constraint that ...

We present a statistical study of the presence of galaxy warps in the Hubble deep fields. Among a complete sample of 45 edge-on galaxies above a diameter of 1\\farcs3, we find 5 galaxies to be certainly warped and 6 galaxies as good candidates. In addition, 4 galaxies reveal a characteristic U-warp. Compared to statistical studies of local warps, and taking into account the strong bias against ...

The radial distributions of temperature, density, and gas entropy among cool-core clusters tend to be quite similar, suggesting that they have entered a quasi-steady state. If that state is regulated by a combination of thermal conduction and feedback from a central active galactic nucleus (AGN), then the characteristics of those radial profiles ought to contain information about the spatial ...

The EXPORT consortium carried out in 1998-1999 photo-polarimetric and spectroscopic monitoring over 74 Pre-Main Sequence (PMS) and Main Sequence (MS) stars with infrared excesses, 43 of them showing the H? line in emission. We have measured the equivalent widths (EWs) of the H?, [OI]6300, HeI5876 and NaID lines in 370 intermediate resolution optical spectra, obtained along four different observing ...

A cosmic X-ray spectroscopy experiment onboard the Orbiting Solar Observatory 8 (OSO-8) observed Her X-1 continuously for approximately 8 days. Spectral-temporal correlations of the X-ray emission were obtained. The major results concern observations of iron band emission, spectral hardening (increase in effective x-ray temperature) within the X-ray pulse, and a transition from an X-ray low state ...

The giant planets in the Solar System each have two groups of satellites. The regular satellites move along nearly circular orbits in the planet's orbital plane, revolving about it in the same sense as the planet spins. In contrast, the so-called irregular satellites are generally smaller in size and are characterized by large orbits with significant eccentricity, inclination or both. The ...

The partitioning and incorporation mechanism of Ni and Ba in a ferromanganese nodule from Lake Baikal were characterized by X-ray microfluorescence, microdiffraction, and absorption spectroscopy. Fe is speciated as goethite, and Mn as romanechite (psilomelane) and 10 �-vernadite (turbostratic buserite) with minor 7 �-vernadite (turbostratic birnessite). Barium is ...

I present a relativistic covariant version of the Bohmian interpretation of quantum mechanics and discuss the corresponding measurable predictions. The covariance is incoded in the fact that the nonlocal quantum potential transforms as a scalar, which is a consequence of the fact that the nonlocal wave function transforms as a scalar. The measurable ...

We have undertaken a theoretical study of the impact of the accumulating envelopes on the thermal state of the underlying white dwarf (WD). This has allowed us to find the equilibrium WD core temperatures, the classical nova ignition masses and the thermal luminosities for WDs accreting at rates of 10-11 - 10-8M? yr-1. These accretion rates are most ...

The Lewisian Complex of northwestern Scotland is an Archaean basement terrain that was reworked during the Proterozoic. Previous geochronological studies have established that the complex represents an entirely new crustal addition during late-Archaean times, and the difference between a Sm-Nd accretion date of 2920 + or - 50 Ma and a Pb/Pb metamorphic date of 2680 + or - 70 ...

The ordinary chondrites (OCs) comprise three petrographic series, each ranging from type 3 (the UOCs), with distinct chondrules, little crystalline intergrowth and unequilibrated minerals, to type 6 or 7, in which chondrules have largely disappeared into a granular textured fabric with little mineralogical disequilibrium. There are conflicting interpretations of the textural ...

The dynamical and radiative consequences of disk accretion onto magnetic T Tauri stars (TTS) are examined using the Ghosh and Lamb model. It is shown that a prolonged disk accretion phase is compatible with the low rotation rates measured in these stars if they possess a kilogauss strength field that disrupts the disk at a distance of a few stellar radii ...

In the last several years, multiwavelength monitoring programs have allowed us to develop a general description of the observational characteristics of accreting black holes as they journey through their outburst cycles. Driven seemingly to a large extent by the accretion rate, these sources display an almost predictable series of physical changes which ...

The Mira AB system is a nearby (~107 pc) example of a wind accreting binary star system. In this class of system, the wind from a mass-losing red giant star (Mira A) is accreted onto a companion (Mira B), as indicated by an accretion shock signature in spectra at ultraviolet and X-ray wavelengths. Using novel imaging techniques, we ...

It is shown arbitrary gauge as the result of the long wavelength and lowest order approximation of fields.

We present evidence from tungsten (W) isotopic measurements consistent with the presence of live 182Hf (T1/2 = 9 Ma) in the early solar system. This is based on the observation of a well-resolved deficit of about four parts in ten thousand in the ratio 182W/183W in W separated from the Toluca iron meteorite. This deficit is interpreted as an excess in the terrestrial standard ...

We summarize the transactional interpretation of quantum mechanics (TI) and consider various points concerning the TI and its relation to the Copenhagen interpretation (CI). Questions concerning mapping the TI onto the CI, of advanced waves as solutions t...

The new interpretation of quantum mechanics is based on a complex probability theory. An interpretation postulate specifies events which can be observed and it follows that the complex probability of such events is, in fact, a real positive number. The tw...

The Einstein-Podolski-Rosen 1935 postulates, implying locality, reality and causality, are confronted with J.S. Bells 1964 theorem on theories with hidden parameters. A modern formulation of the Copenhagen interpretation of quantum mechanics is presented ...

Motion Interpretation of Trochoid Paths with a Rotational Motion Sensitive Network and Attention, 1994 Abstract This paper present a simulation of motion interpretation of trochoid path generated involves two mechanisms. First, the extraction of relative motion in a group motion and second the presence

In this study, the mechanics of forearc basins will be the object of a numerical investigation to understand the relationships between the wedge deformation and forearc basin formation. The aim of this work is to gain insight into the dynamics of the formation of the forearc basin on top of a deforming accretionary wedge, including the mechanism of ...

Existing International Ultraviolet Explorer (IUE) and American Association of Variable Star Observers (AAVSO) archive data was used to accomplish a large scale study of what happens to the ultraviolet flux of accretion disk systems during the quiescent intervals between outbursts and how it relates to the preceding outburst characteristics of amplitude and width. The data ...

We present an analysis of the long-term evolution of outbursts in the neutron star soft X-ray transient GRS 1747-312. Observations taken from ASM/RXTE, in the 1.5-12 keV passband, are utilized. We reveal a cyclic behavior in the residuals of the outburst recurrence time with respect to the mean value of TC = 136 � 2 days. The profile of this cycle is approximately sinusoidal; the remaining ...

We have analyzed 866 RXTE observations of the 2006-2007 outburst of the accreting neutron-star XTE J1701-462, during which it evolves from super-Eddington luminosities to quiescence. It first resembles the Cyg X-2 subgroup of Z sources, with frequent excursions on the horizontal and normal branches (HB/NB). The source then decays and evolves to the Sco X-1 subgroup, with ...

We have analyzed 866 Rossi X-ray Timing Explorer observations of the 2006-2007 outburst of the accreting neutron star XTE J1701 -462, during which the source evolves from super-Eddington luminosities to quiescence. The X-ray color evolution first resembles the Cyg X-2 subgroup of Z sources, with frequent excursions on the horizontal and normal branches (HB/NB). The source then ...

The distribution and resolution of thermal events and associated igneous activity can discriminate between tectonic processes that form orogenic terrains, i.e., accretion of terranes, overthrusting of terranes versus thrust stacking within terranes. Reinterpretation of regional tectonics (Higgins et al., 1984) coupled with the authors interpretation of the ...

Chandra and XMM data have revealed narrow and highly redshifted Fe K emission lines in a handful of AGN. Rapid flux variability and energy shifts of the lines have lead to speculations for their origin ranging from hotspots on the accretion disk to emission from decelerating ejected blobs of gas traveling close to the escape velocity. Whichever scenario proves true, these ...

... can be interpreted to mean protection from fire, chemical degradation, mechanical wear, weathering, as well as biological attack. ... ...

and the difficulties of measurement interpretation that must be thoroughly investigated before such a standard can be proposed. ...

Language: English ...

... AS ESSENTIAL ELEMENTS IN INTERPRETING EXPERIMENTAL DATA AND IN DESCRIBING THE DAMAGE TOLERANCE OF THE F-111 FLEET. ...

We investigate the role of the compact object in the production of jets from neutron star X-ray binaries. The goal is to quantify the effect of the neutron star spin, if any, in powering the jet. We compile all the available measures or estimates of the neutron star spin frequency in jet-detected neutron star X-ray binaries. We use as an estimate of the ranking jet power for each source the ...

Knowledge of convergent margin systems evolved from hypothesis testing with marine geophysical technology that improved over decades. Wegener's drift hypothesis, Holmes mantle convection, and marine magnetic anomaly patterns were integrated into an ocean spreading concept that won wide acceptance after ocean drilling confirmed the crustal younging trend toward the Mid-Atlantic ridge. In ...

The continental evolution of eastern North America, especially the Appalachian Geologic Province (1200 Ma to present) preserves a complete geologic record of two successive supercontinent assemblies and dispersals, including evidence for rifting and development of passive margins, accretion of island arcs, ribbon continents, continental and oceanic blocks. High resolution SIMS ...