Anomalous Mass Research Articles

Topography at the core‐mantle boundary

Analysis of the Earth's gravity field using ratio of gravity to geoid (g/N) and cumulative degree contribution curve techniques improves resolution of the mass, depth, and dimensions of anomalous mass sources within the planet. The source for four of the ten major geoid anomalies of the Earth has large contributions from harmonic degrees 2 and 3, lie at the core‐mantle boundary, and the greatest has a mass anomaly of 4.2·1022 grams. That boundary has a density contrast (4.4 gm/cm³) which is greater than at any other location, including the contrast at the Earth's surface with space. Thus, relatively small vertical undulations of that boundary produce very large mass anomalies. Topographic relief of less than 3 km at the core‐mantle boundary occurs, and accounts for the existence of the largest geoid anomalies occurring on the Earth.

Squaraine chemistry. On the anomalous mass spectra of bis(4-dimethylaminophenyl)squaraine and its derivatives

The electron impact (EI) mass specra of bis(4-dimethylaminophenyl)squaraine 1 and its derivatives 2–14 have been studied. Ions of mass number higher than the molecular ion, which are shown to be precursors of fragment ions of lower mass numbers, are observed. From the structure–property relationship, these ions are assigned to [Formula: see text] and [Formula: see text] where CH2R is the alkyl group in the N,N-dialkylanilino moiety of squaraine. Evidence is provided that the formation of [Formula: see text] and [Formula: see text] is the result of alkyl transfer and H transfer reactions within a squaraine aggregate rather than intermolecular vapor phase reactions in the mass spectrometer. This molecular aggregate is later shown to be a trimer by analysis of metastable ion data and chemical ionization mass spectrometry. The fragmentation sequence of this trimeric species is elucidated with the assistance of metastable ions. Results show that the trimer may break down to monomelic and dimeric species upon electron impact; alternatively, the four-membered ring of the central squaraine in the trimer may cleave to generate two species of approximately equal mass number. These two species usually dominate the mass spectrum and further fragment into [Formula: see text] and [Formula: see text] Detailed fragmentation schemes for [Formula: see text] and [Formula: see text] are proposed and discussed.

Evidence for mass loss from IRAS observations of classical Cepheids

Mass loss from classical Cepheid variables is suspected on two grounds. First, it may provide an explanation of the persistent discrepancy between estimates of Cepheid masses based on the theories of stellar pulsation and of stellar evolution1. Second, theoretical models of pulsating atmospheres2 suggest that a pulsation mechanism may be responsible for causing, or enhancing, mass loss from Cepheids. In order to test these hypotheses, evidence of anomalous mass loss was sought by making a comparison between the infrared emission of Cepheids and that of nonvariable supergiants in the same luminosity and effective temperature range. A search of the IRAS (Infrared Astronomy Satellite) catalogue3 found a number of Cepheids and stable supergiants which showed emission in at least one of the IRAS wavelength bands. Some long-period Cepheids showed infrared excesses with respect to their non-pulsating counterparts, while emission from Cepheids with periods of less than 10 days was comparable to the levels seen in the stable supergiants. Mass loss rates of up to 7 × 10−7 M⊙ yr−1 were derived from the infrared excesses, which is sufficiently high to have a major effect on the evolution of these stars.

Linear inversion of gravity data using the spectral expansion method

Inversion of gravity anomalies in terms of an anomalous mass distribution with irregular outline but uniform density leads to a nonlinear inverse problem. An alternative approach based on the thin‐sheet approximation can, however, be formulated as a linear inverse problem provided the structures are two‐dimensional. The anomalous mass is represented by a thin sheet, which is located at a depth [Formula: see text] and is divided into M strips with N < M data points. Thus, an underdetermined system of linear equations is obtained which is solved by the spectral expansion method for the surface density distribution of each segment. This set of parameters is then transformed into a prismatic structure with variable depth but uniform density. The modeling procedure involves a noniterative method. A gravity problem is investigated, and the solution obtained compares well with previous interpretations.

Dynamic and figure parameters of Venus and Mars

Parameters of the best-fitting tri-axial ellipsoids representing external equipotential surfaces of Venus and Mars have been determined from satellite data. The dynamic consequence of the equatorial flattening of Venus has been discussed from the point of view of the s.c. synodic resonance rotation. The major gravitational anomalies of Venus have been interpreted, space locations and magnitudes of anomalous masses determined and their contribution to the second zonal Stokes' constant in the gravitational potential computed. The conclusions were done: The figure of the aphroditoid is strange even if there is a relatively small polar flattening; an equatorial “disc” of Venus is enormous. Recent space data do not support hypothesis that the Earth controls the spin of Venus.

Anomalous mass numbers in quadrupole mass spectrometers (QMS) at very low pressures

In this work, the results of mass spectrometric studies of the residual vacuum in a uhv all metal system are presented. H +, O + and F + ions arising from surface effects are found. The abundance of F + is extremely high, as compared with previous work. Surface spectra on a tungsten sample are also presented for comparison, as well as changes in the gases in the volume and surface ions on introducing H 2O into the system. Surface ions from the W sample show the high dissociation of H 2O (H + and O + ions), but no OH + ions are found. Thermal treatment of the W surface shows that F + has two desorption states. Ion energy distribution maxima for surface species from the tungsten sample are 4.4 eV for H +, 4.5 eV for F + and 10.2 eV for O +.

Identification of mantle and lithospheric components of the gravity field by isostatic gravity anomalies

All anomalous masses of the Earth are reflected in the free air gravity anomalies and the geoidal undulations. The low viscosity of the asthenosphere significantly reduces the possibility of existence of density inhomogeneities in the layer. This fact provides some physical basis for the separation of the gravity field anomalies. It has been shown by power spectrum analysis of the free air anomalies and gravity field of isostatically compensated model of the lithosphere for the North Atlantic and adjacent areas of America, Europe and Mediterranean, that the attraction of isostatically compensated model is significant for any wave length of the field. It causes significant error in the interpretation if long wavelength constituents of the free air gravity anomalies are considered as a field of deep anomalous masses. The isostatic anomalies und isostatic geoid are free from the influences of isostatically compensated lithosphere. The characteristic feature of the isostatic anomalies power spectrum is a pronounced minimum at the wavelength of about 1000 km. The relative homogeneity of the asthenosphere may explain this minimum. It means that principal density inhomogeneities of the Earth’s interior are separated by the asthenospheric layer. Such a minimum has not been observed at the power spectrum of free air anomalies being masked by corresponding wavelength of the field of isostatically compensated lithosphere. Isostatic anomalies that reflect the differences between the real structure of the lithosphere and its isostatically compensated model have wavelengths less than 1000 km. Isostatic anomalies with the wavelength more than 1000 km reflect the attraction of density inhomogeneities situated under the level of isostatic compensation. The basic features of power spectrum of isostatic anomalies are the same for oceanic and continental areas. The method based on Kolmogorov — Wiener filtration which consideres statistical characteristics of the field has been developed to divide the isostatic gravity anomalies into lithosphere and mantle components. For the North Atlantic and adjacent areas the field of mantle inhomogeneities has been determined.

Ultraviolet spectroscopic observations of some Be stars of later type and A-F type shell stars

High-dispersion IUE spectra of 18 later type Be and A-F type shell stars as well as eight standard nonemission line stars have been analyzed for anomalous ionization and mass loss effects. It is found that superionization in the Be stars extends to the latest spectral subtypes but does not seem to be present in the A-F type stars. The superionized lines in the Be stars appear to be correlated with v sin i. Asymmetrical or violet-displaced resonance lines suggesting mass loss are observed in all the Be stars except one, in some of the standard stars, but not in the A-F stars. Lower limits to the mass loss rates computed from Si IV lines range between 5.3 x 10 to the -12th and 3.5 x 10 to the -11th solar masses/yr, with Be shell stars showing the largest values. Mass loss is correlated with luminosity and effective temperature but not with rotation.

The electric sub-band structure of electron accumulation layers in InSe from Shubnikov-de Haas oscillations and inter-sub-band resonance

In bulk InSe crystals grown by the Bridgman method, electron accumulation layers are formed in the vicinity of stacking faults with charged impurities adsorbed to the defect plane. Shubnikov-de Haas experiments show that the 2D electron gas in InSe observed at low temperatures has a density of 1012 cm-2 and that several dielectric sub-bands are occupied. The g-factor is enhanced by electron-electron interactions. The optical absorption was studied in the frequency range 3-20 meV in perpendicular and tilted magnetic fields up to 8T. The cyclotron resonance at Eres=h(cross) omega c, the intersubband resonance at Eres=E01 and the combined resonance at Eres=E01+h(cross) omega c, are all observed for both parallel and tilted polarisation, where E01 is equal to the sub-band separation as deducted from the Shubnikov-de Haas periodicities. With increasing magnetic fields the exciton-and depolarisation-shifted resonance E01 approaches the true sub-band splitting E01, and is the same time reduced in amplitude. Absorption due to bulk 1s-2p transitions in isolated shallow donors is also observed. The 2p level shows a three-dimensional Zeeman splitting (h(cross) omega c)3D with a weak anomalous mass anisotropy as observed in cyclotron resonance measurements of bulk carriers at temperatures of 30-100K. The effective electronic Rydberg is in agreement with results of exciton spectra.

Energy equilibration and anomalous mass drift in heavy ion collisions

The lack of mass drift towards symmetry observed in many Kr-induced reactions, and the excessive mass drift towards larger asymmetry in Ne, Ar-induced reactions, is explained in terms of a dynamical driving force towards larger mass asymmetries due to the attempt of the smaller fragment to contain its temperature gradient with respect to the heavy fragment.

Rock density from borehole gravity surveys

The borehole gravity meter (BHGM) is recognized as an important logging tool for obtaining formation bulk density. In general, however, the difference between two gravity observations vertically separated in a well leads to an apparent and not the actual bulk density. BHGM‐derived apparent densities are equal to the formation bulk densities when the instrument passes through beds which are horizontal, infinitely extended laterally, uniformly thick, and constant in density. For many applications, departures from these assumed conditions are so slight that their effects can be ignored, and the BHGM essentially yields bulk density with a large radius of investigation. In the presence of anomalous masses, significant distortion in formation bulk density is possible. The apparent density anomaly produced in the well by an elongated, offset density contrast is proportional to the angle subtended by the density‐change interface. For a density‐change boundary having circular symmetry with respect to the well, the apparent density anomaly at the center of the bed is proportional to the sine of the subtended angle. Because the distortion in bulk density is the same above a horizontal boundary as it is just below (in the limit, at the boundary, for a normally incident well), an abrupt change in apparent density is equal to the real density change at the boundary. This change in density, termed “the Poisson jump,” is independent of geometry; our ability to measure it, however, is a function of station location with respect to the geologic bodies. Two methods are suggested for obtaining bulk densities from BHGM apparent densities: (1) by obtaining two stations just outside as well as just within the zone of interest, the Poisson jump can be approximated and added to an independent density source (e.g., the gamma‐gamma log), and (2) the apparent density anomaly within the formation of interest can be derived by modeling (perhaps based on seismic or well data) and added to the BHGM‐determined densities. Thinner beds can be studied with the BHGM than generally believed, even with much greater station spacing.

Percolation Characteristics in Discontinuous Thin Films of Pb

The geometrical features of discontinuous Pb films are analyzed in terms of the scaling theory of percolation. Above the percolation threshold it is shown that the infinite cluster as well as the backbone has an anomalous mass distribution up to a length of the order of the percolation correlation length (${\ensuremath{\xi}}_{p}$), corresponding to that of self-similar objects. Above ${\ensuremath{\xi}}_{p}$, the mass distribution is homogeneous. Below the percolation threshold, the cluster statistics agrees with scaling theory.

Extension in the Rio Grande Rift

A positive gravity anomaly along the axis of the Rio Grande rift reflects a volume of anomalous mass added at the base of the crust and intruded into the crust. Part of this volume can be associated with vertical uplift of the crust. The remainder of this anomalous volume, plus the volume of surficial graben fill, can be associated with horizontal crustal extension. The volume of crustal uplift in the Rio Grande rift is unknown, but this term can be eliminated by means of an independent equation provided by assumption of generalized isostatic equilibrium. The volume and mass equations combined provide a solution for extension of the crust in terms of the following parameters: total anomalous mass deficiency in the mantle lithosphere, total anomalous mass excess in the crust and its density contrast, total anomalous mass deficiency of surficial graben fill and its density contrast, and the volume of material eroded from the uplift. Using standard density estimates and masses determined by equivalent‐source modeling of gravity profiles, I obtained 1‐km extension at 37°N (Colorado‐New Mexico border), 13‐km extension at 35°N (Albuquerque, New Mexico), and 24‐km extension at 33°N in southern New Mexico. These estimates are of necessity very poorly constrained and may be as much as ±60% in error. Taking results at face value, the best fitting Euler pole occurs at about 41°N, in north central Colorado. The calculated opening angle is 1.32°. For an approximately 30‐m.y. duration of the extensional system (late Oligocene to the present), calculated average angular velocity is 7.8×10−4 rad/m.y.; calculated average spreading half‐rate at 33°N (for example) is a stately 0.04 cm/yr. The ratio of extension to uplift increases southward.

Reply by the author to G. D. Garland.

Although the Tokaanu experiment does contradict the proposal that the gravitational constant G increases with scale, the result is not significant. The standard error in the least‐squares adjustment is at least 1 percent, which exceeds the predicted variation in G. The uncertainty in mean density is nearer 5 percent. Gravity data with sufficient precision to test for a scale effect in G are obtainable; the main problem appears to be the uncertainty in density determinations. Stacey et al (1981) made a least‐squares determination of G using gravity and density measurements from a mine. However, the pattern of residuals obtained indicated the presence of anomalous masses not adequately accounted for by their density averaging. The method I have used which models the spatial variation in density offers the possibility of obtaining a least‐squares fit for G with a satisfactory residual distribution. However, the problem of the effect on bulk density of joints and voids not sampled in hand specimens remains.

Relativistic corrections to dipole decay amplitudes in quarkonium

We study the leading relativistic correction to the dipole amplitude for a radiative transition between bound states of two spin-(1/2) particles with arbitrary anomalous magnetic moments and masses. For the part of the correction which corresponds to a modification of the dipole operator, and which is spin-dependent, our results reduce, in the equal-mass case, to those given by earlier authors. There is another part, which arises from perturbing the initial and final wave functions with the fine-structure operator. We give the results of a numerical calculation which indicates that in the case of charmonium the wave-function effect can be larger than that arising from the dipole-operator modification.

The anomalous mass dimension to two loops in quantum chromodynamics

A calculation of the anomalous mass dimension, δ, to second order in quantum chromodynamies, done in the zero-mass renormalization scheme of Weinberg, is presented. By different limiting procedures we obtain two different results for δ giving an explicit example of renormalization scheme dependence.

HD 208095 : DISAPPEARANCE OF THE LAST OF THE OVERMASSIVE DETACHED BINARIES.

ABSTRACT The late B-type spectroscopic binary, HD 208095, is removed from the diminishing ranks of spectroscopic binaries with apparently anomalous masses by means of analysis of a new set of spectrograms. The minimum masses (3.5 and 3.2 solar masses) are close to the masses expected for the spectral types. The more massive star has the slightly earlier type. While the line widths in the spectrum of the cooler component of this detached system are consistent with equality of orbital and rotational periods, the lines of the hotter component are considerably broader.

Origin of anomalous mass renormalizations inferred from proximity tunneling experiments

Experiments with thin Ag layers (${d}_{N}\ensuremath{\sim}100\ensuremath{-}700$ \AA{}) backed by thicker Pb (${d}_{S}\ensuremath{\sim}3500$ \AA{}) have led Khim and Tomasch to infer large effective renormalizations for Ag that increase with decreasing ${d}_{N}$, even though the electron-phonon interaction presumably retains its bulk character. Arnold has recently shown that dirty proximity superconductors violate Anderson's theorem and that, in this regime, the usual treatment of elastic scattering is inappropriate for Andreev interference phenomena. He finds that both the pairing potential, ${\ensuremath{\Delta}}_{N}(E)$, and the effective layer renormalization, ${Z}_{N}(E)$, are influenced strongly by scattering. Our reanalysis, based on Arnold's theory and on Gallagher's compound-resonance theory, assumes bulk behavior for the Ag electron-phonon interaction. We obtain successful quantitative agreement with the Ag-Pb data when the Ag mean free path nearly equals the Ag film thickness. Our best estimates of the dressed Fermi velocities are ${v}_{\mathrm{FS}}^{*}(\mathrm{Pb})=(0.72\ifmmode\pm\else\textpm\fi{}0.06)\ifmmode\times\else\texttimes\fi{}{10}^{6}$ m/s and ${v}_{\mathrm{FN}}^{*}(\mathrm{Ag})=(1.07\ifmmode\pm\else\textpm\fi{}0.06)\ifmmode\times\else\texttimes\fi{}{10}^{6}$ m/s.

On the mass-independent renormalization scheme

A calculation of the second order coefficient of the anomalous mass dimension function γm of Weinberg is made in quantum electrodynamics using the techniques of Sen and Sundaresan. The role of this quantity in perturbation theory is discussed from the point of view of the "Principle of Minimal Sensitivity" criterion of Stevenson.

Regional compensation of subducted lithosphere: effects on geoid, gravity and topography from a preliminary model

It is proposed that the anomalous mass of subducted lithospheric slabs is partially compensated by two mechanisms: (a) by stresses transmitted up the slab to the surface lithosphere, causing the trench, and (b) by stresses transmitted through the mantle wedge overlying the slab, which cause a broad shallow depression. Results calculated from a preliminary two-dimensional model show that it can give a first-order account of observed topography, gravity and geoid anomalies. In particular, the model can reconcile the large mass anomaly predicted for the slab by thermal conduction theory with the smaller than expected gravity and geoid anomalies. Preliminary results indicate substantial compensation by mechanism (a), implying rather large stresses at the top of the slab: these could be important for theories of earthquake mechanisms and plate driving mechanisms. Roughly 50% of the possible compensation by mechanism (b) is indicated: the resulting depression, the order of 500 m deep and over 500 km wide, could explain anomalously deep marginal basins and some marine transgressions of continents.