Mutually interacting Tachyon dark energy with variable $G$ and $\Lambda$

In this paper we consider Tachyonic scalar field as dark energy with interaction between components in the case of variable $G$ and $\Lambda$. We assume a flat Universe with specific form of scale factor and study cosmological parameters numerically and graphically. Statefinder analysis also performed as well. In the special choice of interaction parameters we succeed to obtain analytical expression of densities. We find that our model will be stable in the late stage but there is an instability at the early Universe.
Comment: 17 pages, accepted by Research in Astronomy and Astrophysics (RAA). arXiv admin note: text overlap with arXiv:1402.2592 by other authors