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Probing the gravitational Faraday rotation using quasar X-ray microlensing
1Research Computing Center, Dirac Science Library, Room 150-F, Florida State University, Tallahassee, FL 32306, USA.
Scientific Reports
|November 18, 2015
Summary
Gravitational Faraday rotation, predicted decades ago, can now be detected. Monitoring X-ray polarization of microlensed quasars offers new evidence for general relativity and strong gravity in quasars.
Area of Science:
- Astrophysics
- General Relativity
- X-ray Astronomy
Background:
- Gravitational Faraday rotation was theoretically predicted in the 1950s.
- No practical methods currently exist for its measurement.
- Measuring this effect provides crucial tests for general relativity, especially in strong gravity regimes.
Purpose of the Study:
- To propose a practical method for detecting gravitational Faraday rotation.
- To provide new observational evidence supporting general relativity.
- To confirm the strong gravity nature of X-ray emission from quasars.
Main Methods:
- Simulating X-ray polarization light curves of gravitationally microlensed quasars.
- Analyzing variations in polarization degree and angle during caustic-crossing events.
- Utilizing data from cosmologically distant quasars lensed by foreground galaxies or clusters.
Main Results:
- The first simulations of quasar X-ray microlensing polarization light curves predict rapid, concurrent variations in polarization and flux during caustic crossings.
- These predicted variations are directly linked to gravitational Faraday rotation.
- The study establishes a feasible method for detecting this elusive effect.
Conclusions:
- Monitoring X-ray polarization of gravitationally microlensed quasars is a viable method for detecting gravitational Faraday rotation.
- This detection will offer compelling evidence for the validity of general relativity in strong gravitational fields.
- Confirmation of gravitational Faraday rotation will validate models of strong gravity in quasar X-ray emission.
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