Radiation Pattern for a Multiple-Element HFGW Generator
Abstract
We calculate the values for the High-Frequency Gravitational Wave (HFGW) radiation pattern for a multiple-element HFGW generator in the "far field," that is the field many wavelengths away from the generator. We extend-Baker, Davis and Woods (2005) for a single GW-emission pair to include an in-phase, linear array of N such pairs as discussed in Baker, Stephenson and Li (2008). We calculate new values for the variable K in Baker, Davis and Woods (2005) by decreasing the integration interval of Θ from 10° to 1°. This provides us with a K value of increased accuracy. The improved K has a value of 7.6×10-7 deg-2 and is used to find the power intensity, I(Θ), of a single GW source in terms of watts per square degree over the radiation-pattern cap The Θ half-power-point angle for a single GW-emission pair at their mid-way-point focus is also recalculated and found to be 47.5°. We utilize the result of Romero and Dehnen (1981) and Dehnen and Romero (2003) for an increase in HFGW flux (in a linear array of N in-phase radiation elements) proportional to N2. This result is employed to compute the half-power-point angle, idealized radiation cap area and the HFGW flux/power-of-a-single-radiation-element at a distance of several wavelengths away, for example one meter from the end of a linear and a double-helical array in Wm-2 as a function of N. The notional picture shown of an idealized needle-like radiation beam is in the far field. It is described at a distance far enough from the generator that it is beyond the conventional diffraction limit of a beam's radiation-pattern cap area. It is found that the HFGW flux calculated is small, but that the Li-Baker detector may be capable of sensing the HFGWs generated in a laboratory setting.
- Publication:
-
Space, Propulsion & Energy Sciences International Forum: SPESIF-2009
- Pub Date:
- March 2009
- DOI:
- 10.1063/1.3115569
- Bibcode:
- 2009AIPC.1103..582B
- Keywords:
-
- 95.85.Sz;
- 03.50.De;
- 98.80.Bp;
- Gravitational radiation magnetic fields and other observations;
- Classical electromagnetism Maxwell equations;
- Origin and formation of the Universe