- Access by Xinjiang University
Aberration in gravitational lensing
Phys. Rev. D 78, 083003 – Published 8 October, 2008
DOI: https://doi.org/10.1103/PhysRevD.78.083003
Abstract
It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily interpreted in terms of aberration of light rays. Both radial and transverse motions with relativistic velocities are considered. The lens equation is derived by first considering geodesic motion of photons in the rest-frame Schwarzschild space-time of the lens, and, then, light-ray detection in the moving observer’s frame. Because of the transverse motion images are displaced and distorted in the observer’s celestial sphere, whereas the radial velocity along the line of sight causes an effective rescaling of the lens mass. The Einstein ring is distorted to an ellipse whereas the caustics in the source plane are still pointlike. Either for null transverse motion or up to linear order in velocities, the critical curve is still a circle with its radius corrected by a factor () with respect to the static case, being the relativistic Doppler shift of the deflector. From the observational point of view, the orbital motion of the Earth can cause potentially observable corrections of the order of the in lensing towards the supermassive black hole at the Galactic center. On a cosmological scale, tangential peculiar velocities of a cluster of galaxies bring about a typical flexion in images of background galaxies in the weak lensing regime but future measurements seem to be too challenging.
Article Text
References (26)
- T. Pyne and M. Birkinshaw, Astrophys. J. 415, 459 (1993).
- S. M. Kopeikin and G. Schäfer, Phys. Rev. D 60, 124002 (1999).
- S. Frittelli, T. P. Kling, and E. T. Newman, Phys. Rev. D 65, 123007 (2002).
- S. Frittelli, Mon. Not. R. Astron. Soc. 340, 457 (2003).
- O. Wucknitz and U. Sperhake, Phys. Rev. D 69, 063001 (2004).
- S. A. Klioner, Astron. Astrophys. 404, 783 (2003).
- D. Heyrovský, Astrophys. J. 624, 28 (2005).
- M. Sereno, Mon. Not. R. Astron. Soc. 359, L19 (2005).
- S. Frittelli, Mon. Not. R. Astron. Soc. 344, L85 (2003).
- M. Sereno and F. De Luca, Phys. Rev. D 78, 023008 (2008).
- E. B. Fomalont and S. M. Kopeikin, Astrophys. J. 598, 704 (2003).
- B. Carter, Phys. Rev. 174, 1559 (1968).
- S. Chandrasekhar, The Mathematical Theory of Black Holes (Clarendon, Oxford, 1983).
- I. Bray, Phys. Rev. D 34, 367 (1986).
- M. Sereno and F. De Luca, Phys. Rev. D 74, 123009 (2006).
- J. M. Bardeen, W. H. Press, and S. A. Teukolsky, Astrophys. J. 178, 347 (1972).
- S. U. Viergutz, Astron. Astrophys. 272, 355 (1993).
- M. Sereno, Phys. Rev. D 77, 043004 (2008).
- C. R. Keeton and A. O. Petters, Phys. Rev. D 72, 104006 (2005).
- P. Schneider, J. Ehlers, and E. E. Falco, Gravitational Lenses (Springer-Verlag, Berlin, 1992).
- F. Eisenhauer, R. Genzel, T. Alexander, R. Abuter, T. Paumard, T. Ott, A. Gilbert, and S. Gillessen, Astrophys. J. 628, 246 (2005).
- M. J. Reid and A. Brunthaler, Astrophys. J. 616, 872 (2004).
- M. Sereno, Mon. Not. R. Astron. Soc. 380, 1023 (2007).
- S. M. Molnar and M. Birkinshaw, Astrophys. J. 586, 731 (2003).
- P. Schneider, in Saas-Fee Advanced Course 33: Gravitational Lensing: Strong, Weak and Micro, edited by G. Meylan, P. Jetzer, P. North, P. Schneider, C. S. Kochanek, and J. Wambsganss (Springer, Berlin, 2006), p. 269.
- D. M. Goldberg and D. J. Bacon, Astrophys. J. 619, 741 (2005).