Scaling relations for width of the power excess of stellar oscillations

Relations between global asteroseismic quantities allow us to derive fundamental stellar parameters. To obtain an insight into solar-like pulsators by an accurate estimate of stellar property requires to explore various scaling relations other than commonly-exploited ones as well as to calibrate the dependence of those over a range of metallicity, mass and evolutionary status of stars. We investigate statistical properties of the width of the Gaussian envelope δν_env for the stellar oscillation power excess by analyzing light curves of 160 stars observed with short-cadence mode by Kepler. We consider the envelope width as important because it measures the efficiency of excitation and damping of solar-like oscillations due to the turbulence in the outer convective envelope. We attempt to fit a single slope power-law and a broken power-law to relations of δν_env with ν_maxand Δν resulting from three different background models, each of which delineates the red-noise of the stellar power spectrum. A goodness of fit is provided in term of χ². In the case of a single slope fit the resulting slope ends up with δν_env/μHz∝(ν_max/μHz)^∼1.47and δν_env/μHz∝(Δν/μHz)^{∼ 1.83} on average, which is somewhat steeper than a previous outcome for red giants. Fitting with two distinct slopes at breaks of ν_max∼850μHz and Δν ∼ 50 μHz, however, suits in the power-law fit than with a single slope in general. Direct fitting in ν_max−n_envplot yields the power-law index +0.53, apparently steeper than previously reported slope from red giants. The origin of breaks can be illustrated by the attributes in the δν_env-distribution of main-sequence and sub-giant stars in the seismic H-R diagram.