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Limits on High-Frequency Gravitational Waves in Planetary Magnetospheres
Tao Liu1, Jing Ren2, Chen Zhang1
1Department of Physics and Jockey Club Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong S.A.R., People's Republic of China.
Physical Review Letters
|April 13, 2024
Summary
Nearby planets like Earth and Jupiter can serve as gravitational wave detectors. This study presents initial limits for detecting high-frequency gravitational waves (HFGWs) and their conversion to photons in planetary magnetospheres.
Area of Science:
- Cosmology and Astrophysics
- Fundamental Physics
- Planetary Science
Background:
- High-frequency gravitational waves (HFGWs) offer insights into the early Universe and dense, small-scale astronomical objects.
- Detecting HFGWs is challenging due to their nature and the limitations of current observational methods.
Purpose of the Study:
- To explore the potential of using nearby planets, such as Earth and Jupiter, as natural laboratories for HFGW detection.
- To investigate the conversion of HFGWs into detectable signal photons within planetary magnetospheres.
- To establish initial detection limits and project future sensitivities for HFGW observations using planetary environments.
Main Methods:
- Utilizing data from existing low-Earth-orbit satellites to set preliminary HFGW detection limits.
- Analyzing data from the Juno mission orbiting Jupiter for HFGW-photon conversion signals.
- Modeling the GW-photon conversion process and signal flux distribution within planetary magnetospheres.
Main Results:
- Presented the first observational limits for HFGWs in specific frequency bands using a low-Earth-orbit satellite.
- Reported initial detection limits from the Juno mission, providing new constraints for HFGW searches.
- Demonstrated encouraging results for a broad frequency range, including previously unexplored portions of the spectrum.
Conclusions:
- Planetary magnetospheres offer a viable and promising avenue for detecting HFGWs.
- The long path for GW-photon conversion and wide signal distribution enhance detection prospects.
- Future dedicated missions could significantly improve HFGW detection sensitivities using this approach.
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