Program: GS-2013A-Q-99

Title:Testing the cosmological model with Very Long Baseline Interferometry
PI:Oleg Titov
Co-I(s): Dick Hunstead, Dave Jauncey, Helen Johnston, Laura Stanford, Tapio Pursimo

Abstract

1200 radio quasars are observed regularly by the International VLBI Service, IVS, to define and maintain the International Celestial Reference Frame, ICRF. We have presented evidence for large scale proper motions. While the dipole effect is consistent with theoretical prediction, the quadrupole effect, at a level in excess of 5 muas/year, presents a serious challenge to the standard cosmologies. However, we have a concern that our estimates of the spherical harmonics may be influenced by the paucity of IVS quasars with known redshifts in the south. We therefore ask for observing time on the Gemini South telescope with GMOS-S to measure redshifts for 40 southern radio quasars.

Publications using this program's data