A simple analytic solution for tachyon condensation

We evaluate gauge invariants (the action and the gauge-invariant overlap) for numerical solutions satisfying the "$a$-gauge" condition with various values of $a$ in the cubic open bosonic string field theory. We use the level-truncation approximation and an iterative procedure to construct numerical solutions in the twist-even universal space. The resulting gauge invariants are numerically stable and almost equal to those of Schnabl's solution for tachyon condensation. Our result provides further evidence that these numerical and analytic solutions are gauge equivalent.