Three Dimensional Black Hole in the Low Energy Heterotic String Theory

We study the BTZ black holes (2+1 dimensional space-time) in the low energy heterotic string theory (BTZ-Sen BH). This concept requires us to include a non-trivial dilaton $\varphi$ and a 3-form $H_{\mu \nu \rho }$ field. By using the Hassan-Sen transformation and BTZ black hole as a seed solution, we obtain the solution in the string frame. Some properties of the black hole solutions are discussed.