Photoproduction of gravitons in a static magnetic dipole field due to currents

1978 ◽  
Vol 56 (6) ◽  
pp. 801-805 ◽  
Author(s):  
G. Papini ◽  
S. R. Valluri

The cross section for the photoproduction of gravitons in magnetic dipole fields which are due to steady currents is calculated. The approach and the results are compared with the previously studied case in which no currents exist and the potential is represented by a scalar. The calculations in both cases are completely covariant and electromagnetically gauge invariant. The radiative corrections to order [Formula: see text] and [Formula: see text] in the nonrelativistic and relativistic limits are also calculated for dipole and Coulomb fields, respectively. Their evaluation is particularly simple in the transverse traceless gauge for the gravitational field.

Radiocarbon ◽  
1997 ◽  
Vol 39 (1) ◽  
pp. 27-32 ◽  
Author(s):  
John C. Vogel ◽  
Joel Kronfeld

Twenty paired 14C and U/Th dates covering most of the past 50,000 yr have been obtained on a stalagmite from the Cango Caves in South Africa as well as some additional age-pairs on two stalagmites from Tasmania that partially fill a gap between 7 ka and 17 ka ago. After allowance is made for the initial apparent 14C ages, the age-pairs between 7 ka and 20 ka show satisfactory agreement with the coral data of Bard et al. (1990, 1993). The results for the Cango stalagmite between 25 ka and 50 ka show the 14C dates to be substantially younger than the U/Th dates except at 49 ka and 29 ka, where near correspondence occurs. The discrepancies may be explained by variations in 14C production caused by changes in the magnetic dipole field of the Earth. A tentative calibration curve for this period is offered.


2020 ◽  
Vol 5 (2) ◽  
pp. 2419-2426 ◽  
Author(s):  
BhanuKiran Chaluvadi ◽  
Kristen M. Stewart ◽  
Adam J. Sperry ◽  
Henry C. Fu ◽  
Jake J. Abbott

1995 ◽  
Vol 13 (4) ◽  
pp. 427-436 ◽  
Author(s):  
T. Baranyi ◽  
A. Ludmány

Abstract. The influence of the solar corpuscular radiation on weather is demonstrated by characterizing the corpuscular impact by means of the geomagnetic aa-index and the terrestrial response by European temperature data. Considering different spatial and vectorial circumstances the following conclusions can be drawn: 1. the efficiency of the corpuscular impact depends on the Sun-Earth attitude (semiannual fluctuation); 2. this regularity depends on the polarity of the solar main magnetic dipole field; and 3. the whole complex of phenomena also depends on the geographic position - it exists at European middle latitudes but it does not exist in northern and southern Europe. We conclude that the periods of differently or oppositely working mechanisms should be separated in order to recognize the regularities.


Geophysics ◽  
1979 ◽  
Vol 44 (9) ◽  
pp. 1622-1622

The authors have found an error in the paper, “A General Solution for a Spherical Conductor in Magnetic Dipole Field”, Melvyn E. Best and Basil R, Shammas in Geophysics, v. 44, no. 4, p. 781–800 (April 1979), Equation (B-9) should read as follows: [Formula: see text] (B-9) The factor [Formula: see text] was a printing error in the original version.


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