Limits on a stochastic gravitational wave background from observations of terrestrial and solar oscillations

Helioseismology and Asteroseismology: Looking for Gravitational Waves in Acoustic Oscillations

“…Solar low order modes have much larger values than the equivalent ones found in an experimental detector. A similar quantity to χ n was computed by Boughn & Kuhn (1984) and by Siegel & Roth (2011). Unfortunately the comparison of χ n for these models or a resonant-mass detector of constant mass as described by Maggiore (2008) is not trivial to make.…”

“…Preliminary studies of the impact of incoming GW radiation on massive bodies, such as the Earth, Moon, planets and stars were previously presented by several authors (e.g., Dyson 1969;Zimmerman & Hellings 1980;Boughn & Kuhn 1984;Khosroshahi & Sobouti 1997). Boughn & Kuhn (1984) were the first to compute the impact of GW on solar gravity and acoustic modes, for which they also put upper-limits on the stochastic gravitational background from the observed solar oscillations. More recently Siegel & Roth (2011) use an hydrodynamical model to re-evaluate the excitation of solar oscillations by GWs (Siegel & Roth 2010).…”

Stochastic gravitational wave backgrounds

“…The idea of using the Earth itself as a gravitational wave detector goes back to 1969 with a proposal from Freeman Dyson [362]. The use of applying actual data pertaining to motions of the Sun and Earth started as early as 1984 when Boughn and Kuhn [363] analyzed the process by which a gravitational wave background drives the normal modes of a spherical body. Using data of the observed line of sight velocity of the surface of the Sun they were able to constrain Ω GW (f ) to be less that 100 at a frequency of 4 × 10 −4 Hz.…”

(Solar variability observed through changes in solar limb-darkening function and mean diameter)

“…The reported lo confidence level limit on the gravitational flux has a minimum at 4x 10-4 Hz with an energy density per unit logarithmic frequency interval that is --100 larger than the critical energy density required to close the universe. lt should be possible during the nineties to improve on the solar results of Boughn and Kuhn (1984) in several different ways: 1) use measurements of the temperature eigenfunction in lieu of the velocity eigenfunction, 2) work with observed gravity modes and longer-period acoustic modes of the Sun, and 3) take advantage of the rather unique dependence on radial order of the gravitational quadrupole moment for the I,-2 modes Go 1991' Hill and. The disadvantage of working with velocity measurements arises because the energy in a mode excited by gravitational waves is proportional to the square of gravitational quadrupole , 2 moment, (J ) , and the detecnon po,_er sensitivity is proportional to the square of the mode • 2m 2 9 "…”