Rayleigh - Taylor Gravity Waves and Quasiperiodic Oscillation Phenomenon in X-ray Binaries

Accretion onto compact objects in X-ray binaries [black hole, neutron star (NS), white dwarf] is characterized by non-uniform flow density profiles. Such an effect of heterogeneity in presence of gravitational forces and pressure gradients exhibits Raylegh-Taylor gravity waves (RTGW). They should be seen as quasioperiodic wave oscillations (QPO). In this paper I show that the main QPO frequency, which is very close to the Keplerian frequency, is split into separate frequencies (hybrid and low branch) under the influence of the gravitational forces in the rotational frame of reference. The observed low and high QPO frequencies are an intrinsic signature of the RTGW. I elaborate the conditions for the density profile when the RTGW oscillations are stable. A comparison of the inferred QPO frequencies with QPO observations is presented. I find that hectohertz frequencies detected from NS binaries can be identified as the RTGW low branch frequencies. I also predict that an observer can see the double NS spin frequency during the NS long (super) burst events when the pressure gradients and buoyant forces are suppressed. The Coriolis force is the only force which acts in the rotational frame of reference and its presence causes perfect coherent pulsations with a frequency twice of the NS spin.Comment: 14 pages and 2 figures, ApJ in pres

On displacements and intensity changes of atmospheric vortices

Aerological investigations conducted during the last few years have revealed that the long, meandering disturbances characteristic of the middle latitude belt of westerlies in the upper troposphere frequently increase in amplitude until troughs and ridges finally are cut off from the main current, thus forming cold cyclonic vortices on the equatorial side of the west-wind belt and warm anticyclonic vortices on the north side thereof. True vortices, with nearly vertical axes, are thus characteristic phenomena not only of equatorial regions where they appear as tropical cyclones but also of middle latitudes. The middle latitude vortices seem to be phenomena of great stability which have sometimes been observed to persist for several weeks

Editor\u27s Commentary: Relation between variations in the intensity of the zonal circulation of the atmosphere and the displacements of the semi permanent centers of action

Rossby waves! Beta-plane! Here Carl-Gustav Rossby, motivated by observations of weather patterns that move upstream relative to the dominant mid-latitude eastward wind flow, formulates a com-pletely novel linearized theory to account for the tendency for large-scale disturbances to move westward and smaller-scale disturbances to move eastward relative to the winds

Editor\u27s Commentary: On the mutual adjustment of pressure and velocity distributions in certain simple current systems

These are the original geostrophic adjustment papers. Rossby starts out by asking what,if anything, limits the ability for a flow to be in geostrophic balance (to precisely follow pressure contours on a rotating planet). This topic is now a classroom standard, but we often forget how insightful the original articles are..

On the mutual adjustment of pressure and velocity distributions in certain simple current systems, II

In a previous report (Rossby, 1937) the author investigated certain changes in the mass distribution which accompany t he slow lateral diffusion of momentum in a straight parallel current in an unlimited ocean of constant depth. The principal results of this investigation may be st ated as follows:..

On the mutual adjustment of pressure and velocity distributions in certain simple current systems

The writer (J) recently advanced the hypothesis that the horizontal pressure gradients observed in the current systems of the atmosphere and the ocean to a large extent must be interpreted as reactions to the Coriolis\u27 forces impressed upon these systems by the rotation of the earth. Observational support for this point of view was found in the fact that both the temperature-salinity and oxygen-salinity correlation curves obtained from stations on both sides of the Gulf Stream in the region between Nova Scotia and Bermuda are very nearly identical, even though the individual isotherms may drop as much as 700 meters between the slope water basin and the Sargasso Sea. This mass distribution and the resulting pressure distribution are most readily interpreted as the result of a continuous banking process caused by the action of the Coriolis\u27 forces on the moving masses of the Gulf Stream system. Theoretical support was found in a theorem by Taylor (2) ...

Notes on the distribution of energy frequency in surface waves

The behavior of irrotational surface waves of small amplitude in deep water has been thoroughly investigated through theoretical studies extending over a period of more than one hundred years. Waves of this type are therefore particularly well suited for demonstration of the characteristics of energy and frequency distribution and propagation in dispersive media. In the present note a few comments will be made on the distribution of energy with respect to frequency in such waves

On the mutual adjustment of pressure and velocity distributions in certain simple current systems

The writer (Rossby 1936) recently advanced the hypothesis that the horizontal pressure gradients observed in the current systems of the atmosphere and the ocean to a large extent must be interpreted as reactions to the Coriolis’ forces impressed upon these systems by the rotation of the earth. Observational support for this point of view was found in the fact that both the temperature-salinity and oxygen-salinity correlation curves obtained from stations on both sides of the Gulf Stream in the region between Nova Scotia and Bermuda are very nearly identical, even though the individual isotherms may drop as much as 700 meters between the slope water basin and the Sargasso Sea. This mass distribution and the resulting pressure distribution are most readily interpreted as the result of a continuous banking process caused by the action of the Coriolis’ forces on the moving masses of the Gulf Stream system. Theoretical support was found in a theorem by Taylor (1932), according to which any purely two-dimensional motion which can occur in a non-rotating system is equally possible also when the system rotates at uniform speed around an axis normal to the plane of motion, the deflecting forces due to the rotation then being offset by the reaction of the fluid system in the form of a superimposed “Coriolian” pressure field. It is easily shown that this nullification of the Coriolis’ forces is possible only when the prescribed motion is purely two-dimensional..

Relation between variations in the intensity of the zonal circulation of the atmosphere and the displacements of the semi-permanent centers of action

This paper attempts to interpret, from a single point of view, several at first sight independent phenomena brought into focus through the synoptic investigations carried on at the Massachusetts Institute of Technology during the last few years. Since this interpretation is very largely based on a consideration of the changes in vorticity which must occur in vertical air columns which are displaced from one latitude to another and since such vorticity changes play a fundamental role also in Ekman’s general ocean current theory (Ekman 1932), the results would appear to be of enough interest to physical oceanographers to warrrant their publication in this journal..

On the mutual adjustment of pressure and velocity distributions in certain simple current systems, II

In a previous report (Rossby 1937) the author investigated certain changes in the mass distribution which accompany the slow lateral diffusion of momentum in a straight parallel current in an unlimited ocean of constant depth