MISURA DEL GRS SOLARE by Alessandro Cacciani Runa
MISURA DEL GRS SOLARE by: Alessandro Cacciani Runa Briguglio University of Rome “LA SAPIENZA”, Italy Fabrizio Massa INFN sez. Di Roma Paolo Rapex External collaborator James Lo. Presto Edinboro University of Pennsylvania, USA
A sensitive test of Fundamental Physics: General Relativity • Previous results: Vessot & al. 1980: Maser Pound & al. 1960: Effetto Mossbauer Snider 1971: GRS Lo Presto 1991: GRS
How to improve? Instrumental progress such as MOF Technology • Two narrow bands trasmission filter: FWHM= 50 m. A, tuned on a Solar Line • Image detector • High efficiency (30%) • Photon-shot noise limited • Intrinsic stability
Real test of General Relativity requires time dilation effect at a second order 10 -5 -10 -6 times the first order effect. On the sun we expect a second order effect of 10 -5 -10 -6 x 636 m/s 1 mm/s In order to reach this sensitivity, a comparison between the solar MOF signals from two satellites, one near the Earth and the other close to the Sun, will cancel all the unwanted effects, but the GRS alone. The second order signal is in the range of a mm/s (Doppler equivalent), well within the capability of our MOF.
Typical Doppler image with MOF
Doppler signal on the solar equator
Preliminary Analysis
- Slides: 7