Constraining the electric charges of some astronomical bodies in Reissner-Nordstr?m spacetimes and generic r ~(-2)-type power-law potentials from orbital motions

摘要

We put independent model dynamical constraints on the net electric charge Q of some astronomical and astrophysical objects by assuming that their exterior spacetimes are described by the Reissner-Nordstr?m, metric, which induces an additional potential U _(RN) ∝ Q ~2r ~(-2). From the current bounds Δ π{variant}? on any anomalies in the secular perihelion rate π{variant}? of Mercury and the Earth-mercury ranging Δρ, we have {pipe}Q ⊙{pipe} ? 1-0.4 × 10 ~(18) C. Such constraints are ~60-200 times tighter than those recently inferred in literature. For the Earth, the perigee precession of the Moon, determined with the Lunar Laser Ranging technique, and the intersatellite ranging Δρ for the GRACE mission yield {pipe}Q _?{pipe} ? 5-0.4 × 10 ~(14) C. The periastron rate of the double pulsar PSR J0737-3039A/B system allows to infer {pipe}Q NS{pipe} ? 5 × 10 ~(19) C. According to the perinigricon precession of the main sequence S2 star in Sgr A*, the electric charge carried by the compact object hosted in the Galactic Center may be as large as {pipe}Q ?{pipe} ? 4 × 10 ~(27) C. Our results extend to other hypothetical power-law interactions inducing extra-potentials U pert = Ψr ~(-2) as well. It turns out that the terrestrial GRACE mission yields the tightest constraint on the parameter Ψ, assumed as a universal constant, amounting to {pipe}Ψ{pipe} ? 5 × 10 ~9 m ~4 s ~(-2).