SOLAR P-MODE EXCITATION - FURTHER INSIGHT FROM RECENT LOW-L BISON HELIOSEISMOLOGICAL DATA

We present measurements of low-degree solar p-mode velocity powers, en ergies and energy supply rates between similar to 1600 mu Hz and simil ar to 4700 mu Hz, as derived from the analysis of several years of hig h-quality helioseismological data collected by the Birmingham Solar-Os cillations Network (BiSON). For the radial (l = 0) modes, we find that the total energy E per mode (kinetic plus potential) peaks at similar to 3200 mu Hz, reaching approximate to 10(28) erg. The rate at which energy is supplied to the modes (E) over dot = 2 pi Delta nu . E, wher e Delta nu is the FWHM modal line width, is observed to plateau betwee n similar to 3000 and similar to 4000 mu Hz, reaching a maximum of app roximate to 10(23) erg s(-1). At frequencies below the plateau, the su pply rate follows a simple power law with a dependence of (E) over dot proportional to nu(7.0+/-0.4); and at very-high frequencies the data follow (E) over dot proportional to nu(-4.5+/-1.1). These assume modal inertias normalized at T = T-eff; with the mode-mass calculation norm alized at the optical depth of the BiSON observations, the fitted powe r laws in (E) over dot are approximately similar to nu(6.5+/-1.1) and similar to nu(-6.2+/-1.1) respectively.