Equipotential surfaces of close binary star

equipotential surfaces

(ee-kwă-pŏ-ten -shăl, ek-wă-) Imaginary surfaces surrounding a celestial body or system over which the gravitational field is constant. For a single star the surfaces are spherical and may be considered as the contours of the potential well of the star. In a close binary star the equipotential surfaces of the components interact to become hourglass-shaped (see illustration). The surfaces ‘meet’ at the inner Lagrangian point, L₁, where the net gravitational force of each star on a small body vanishes; the contour line through this point defines the two Roche lobes. When both components are contained well within their Roche lobes they form a detached binary system. If one star has expanded so as to fill its Roche lobe it can only continue to expand by the escape of matter through the inner Lagrangian point. This stream of gas will then enter an orbit about or collide with the smaller component. The system is then a semidetached binary: dwarf novae, W Serpentis stars, and some Algol variables are examples. When both components fill their Roche lobes, as with W Ursae Majoris stars, they form a contact binary sharing an outer layer of gas. Matter can then eventually spill into space through the outer Lagrangian point, L₂ .

Collins Dictionary of Astronomy © Market House Books Ltd, 2006

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References in periodicals archive

2 show the correspondence of the PBL features with the main equipotential surfaces [35; [infinity]] = 600 m, [36; [infinity]] = 1600 m and [37; [infinity]] = 4.5 km of the fundamental field F, calibrated on the electron wavelength.

2 show the correspondence of the main stratosphere layers with the main equipotential surfaces [39; [infinity]] = 33 km and [39; 2] = 55 km of the fundamental field F, calibrated on the electron wavelength.

The correspondence of the atmospheric stratification on the Earth, Venus, Mars and Titan with main equipotential surfaces of F demonstrates that the fundamental field affects very different types of physical interaction and is a strong confirmation of global scaling and our model of matter as fractal chain system of oscillating protons and electrons.

Global Scaling of Planetary Atmospheres

Accordingly, the equipotential surfaces of the Earth are curved (Fig.

Where the gravity field is stronger, the distance between the equipotential surfaces is shorter (for example in point A compared to point B on Fig.

Since the equipotential surfaces are not parallel i.e.

Precise levelling data processing near terraced landforms

Two equipotential surfaces of equal and opposite potentials are thus generated defines the profile of the biconical antenna.

Selection of ideal feed profile for asymptotic conical dipole fed impulse radiating antenna

The scalar potential difference [DELTA]F of sequent equipotential surfaces at a given layer k is defined by the difference of continued fractions (1).

As a consequence, the fundamental field of the proton is complementary to that of the electron, because integer logarithms of the proton F correspond to half logarithms of the electron F and vice versa, so that the scaling factor [square root of e] connects similar equipotential surfaces of the proton field with those of the electron field in alternating sequence [8].

Global Scaling of Planetary Systems

Geopotential numbers are determined in GRS 80 normal field, applying the new European gravity system and evaluating non-linearity of GRS 80 normal field equipotential surfaces (Moritz 1988).

To determine normal height differences of points, it is necessary to evaluate non-paralellity of normal field equipotential surfaces as well as real and normal field non-coincidence.

The united geodetic vertical network of Latvia and Lithuania