The S n+1 Action on Spherical Models and Supermaximal Models of Tipe A n−1

2015 ◽  
pp. 173-201 ◽  
Author(s):  
Filippo Callegaro ◽  
Giovanni Gaiffi
Keyword(s):  
Spherical Models

scholarly journals Probing non-spherical dark halos in the Galactic dwarf satellites

2013 ◽  
Vol 9 (S298) ◽  
pp. 411-411
Author(s):  
Kohei Hayashi ◽  
Masashi Chiba
Keyword(s):  
Dark Matter ◽  
Cold Dark Matter ◽  
Milky Way ◽  
Velocity Dispersion ◽  
Line Of Sight ◽  
Spherical Structure ◽  
Spherical Models ◽  
Galactic Satellites ◽  
Best Fitting

AbstractWe construct axisymmetric mass models for dwarf spheroidal (dSph) galaxies in the Milky Way to obtain realistic limits on the non-spherical structure of their dark halos. This is motivated by the fact that the observed luminous parts of the dSphs are actually non-spherical and cold dark matter models predict non-spherical virialized dark halos on sub-galactic scales. Applying these models to line-of-sight velocity dispersion profiles along three position angles in six Galactic satellites, we find that the best fitting cases for most of the dSphs yield not spherical but oblate and flattened dark halos. We also find that the mass of the dSphs enclosed within inner 300 pc varies depending on their total luminosities, contrary to the conclusion of previous spherical models. This suggests the importance of considering non-spherical shapes of dark halos in dSph mass models.

Effect of Savanna windrow wood burning on the spatial variability of soil properties

2021 ◽  
Vol 51 ◽  
Author(s):  
Diogo Neia Eberhardt ◽  
Robélio Leandro Marchão ◽  
Pedro Rodolfo Siqueira Vendrame ◽  
Marc Corbeels ◽  
Osvaldo Guedes Filho ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Spatial Variability ◽  
Spatial Dependence ◽  
Chemical Properties ◽  
Spatial Arrangement ◽  
Nugget Effect ◽  
Tropical Savannas ◽  
Geostatistical Methods ◽  
Exchangeable Ca ◽  
Spherical Models

ABSTRACT Tropical Savannas cover an area of approximately 1.9 billion hectares around the word and are subject to regular fires every 1 to 4 years. This study aimed to evaluate the influence of burning windrow wood from Cerrado (Brazilian Savanna) deforestation on the spatial variability of soil chemical properties, in the field. The data were analysed by using geostatistical methods. The semivariograms for pH(H2O), pH(CaCl2), Ca, Mg and K were calculated according to spherical models, whereas the phosphorus showed a nugget effect. The cross semi-variograms showed correlations between pH(H2O) and pH(CaCl2) with other variables with spatial dependence (exchangeable Ca and Mg and available K). The spatial variability maps for the pH(H2O), pH(CaCl2), Ca, Mg and K concentrations also showed similar patterns of spatial variability, indicating that burning the vegetation after deforestation caused a well-defined spatial arrangement. Even after 20 years of use with agriculture, the spatial distribution of pH(H2O), pH(CaCl2), Ca, Mg and available K was affected by the wood windrow burning that took place during the initial deforestation.

scholarly journals Inverse problem for tripotential measures in the study of buried cavities

1996 ◽  
Vol 39 (1) ◽  
Author(s):  
P. Cosentino ◽  
D. Luzio ◽  
R. Martorana
Keyword(s):  
Apparent Resistivity ◽  
Random Noise ◽  
Source Parameters ◽  
Spherical Shape ◽  
Average Diameter ◽  
Unknown Parameters ◽  
Fundamental Parameters ◽  
Spherical Models ◽  
Source Models ◽  
Biased Estimates

This paper presents a solution to the inverse electrical problem for the interpretation of apparent resistivity anomalies due to empty buried cavities of quasi-spherical shape when tripotential measures are carried out. The anomalies of the apparent resistivities ra,rb andrg,and the composed resistivitiesrmand rt were previously calculated for a sufficient class of spherical models of resistivity anomalies. Then, for the whole class of models, some functionals of spatial distribution of the apparent and composed resistivity were identified and analyzed. They represent the average characteristics of the anomalies and, depending in a simple way on the fundamental parameters of the sources of the anomalies (average diameter and depth), they allow reliable estimates to be determined. Among the studied functionals, those allowing the most stable and less biased estimates of the anomaly source parameters are identified by numerical simulations with random noise perturbed data. Finally the trend of standard deviation and bias of the estimates of the unknown parameters were analyzed by varying the source models and the set of functionals used for the inversion.

A comparison between flat and spherical models of the human head for NIR light propagation

2021 ◽  
Author(s):  
Demian A. Vera ◽  
Maria V. Waks Serra ◽  
Hector A. Gracia ◽  
Guido R. Baez ◽  
Daniela I. Iriarte ◽  
...  
Keyword(s):  
Light Propagation ◽  
Human Head ◽  
Nir Light ◽  
Spherical Models

Family of spherical models with special gravitational properties

2015 ◽  
Vol 41 (3-4) ◽  
pp. 85-94
Author(s):  
B. P. Kondratyev
Keyword(s):  
Spherical Models

scholarly journals Limiting Dynamics for Spherical Models of Spin Glasses at High Temperature

2006 ◽  
Vol 126 (4-5) ◽  
pp. 781-815 ◽  
Author(s):  
Amir Dembo ◽  
Alice Guionnet ◽  
Christian Mazza
Keyword(s):  
High Temperature ◽  
Spin Glasses ◽  
Spherical Models

scholarly journals The Evolution of Shocks in Blazar Jets

2002 ◽  
Vol 19 (1) ◽  
pp. 129-137 ◽  
Author(s):  
Geoffrey V. Bicknell ◽  
Stefan J. Wagner
Keyword(s):  
Rest Frame ◽  
Electron Number Density ◽  
Emission Region ◽  
Number Density ◽  
Electron Number ◽  
Reverse Shock ◽  
Spherical Models ◽  
Infrared Background ◽  
Shock System ◽  
The Magnetic Field

AbstractWe consider the shock structures that can arise in blazar jets as a consequence of variations in the jet flow velocity. There are two possible cases: (1) a double shock system consisting of both a forward and reverse shock, and (2) a single shock (either forward or reverse) together with a rarefaction wave. These possibilities depend upon the relative velocity of the two different sections of jet. Using previously calculated spherical models for estimates of the magnetic field and electron number density of the emission region in the TeV blazar Mkn 501, we show that this region is in the form of a thin disk in the plasma rest frame. It is possible to reconcile spectral and pair opacity constraints for Mkn 501 for Doppler factors in the range of 10–20. This is easiest if the corrections for TeV absorption by the infrared background are not as large as implied by recent models.

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