RadioAstron gravitational redshift experiment: status update

D. A. Litvinov; U. Bach; N. Bartel; K. G. Belousov; M. Bietenholz; A. V. Biriukov; G. Cimo; D. A. Duev; L. I. Gurvits; A. V. Gusev; R. Haas; V. L. Kauts; B. Z. Kanevsky; A. V. Kovalenko; G. Kronschnabl; V. V. Kulagin; M. Lindqvist; G. Molera Calves; A. Neidhardt; C. Ploetz; S. V. Pogrebenko; N. K. Porayko; V. N. Rudenko; A. I. Smirnov; K. V. Sokolovsky; V. A. Stepanyants; J. Yang; M. V. Zakhvatkin

arXiv · 1605.05832

RadioAstron gravitational redshift experiment: status update

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Abstract

A test of a cornerstone of general relativity, the gravitational redshift effect, is currently being conducted with the RadioAstron spacecraft, which is on a highly eccentric orbit around Earth. Using ground radio telescopes to record the spacecraft signal, synchronized to its ultra-stable on-board H-maser, we can probe the varying flow of time on board with unprecedented accuracy. The observations performed so far, currently being analyzed, have already allowed us to measure the effect with a relative accuracy of $4\times10^{-4}$. We expect to reach $2.5\times10^{-5}$ with additional observations in 2016, an improvement of almost a magnitude over the 40-year old result of the GP-A mission.

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D. A. Litvinov, U. Bach, N. Bartel, K. G. Belousov, M. Bietenholz, A. V. Biriukov, G. Cimo, D. A. Duev, L. I. Gurvits, A. V. Gusev, R. Haas, V. L. Kauts, B. Z. Kanevsky, A. V. Kovalenko, G. Kronschnabl, V. V. Kulagin, M. Lindqvist, G. Molera Calves, A. Neidhardt, C. Ploetz, S. V. Pogrebenko, N. K. Porayko, V. N. Rudenko, A. I. Smirnov, K. V. Sokolovsky, V. A. Stepanyants, J. Yang, M. V. Zakhvatkin. 2016-05-19. RadioAstron gravitational redshift experiment: status update. https://arxiv.org/abs/1605.05832

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