What phase should I expect from pauli X?

Here's an example I found that implements the phase estimation algorithm: Here the eigenvector is initialized to the $$|+\rangle$$ state, which is an eigenvector of Pauli X with eigenvalue 1. The measurement result is a complete 0. My question is what the measurement result tells us about the eigenvalue of this system? Since the qubit q[0] is responsible for the time-evolution, is there a way we can tell which Hamiltonian we're simulating? Is it Pauli X?

Thanks!

• You mean q[1] is initialized to |+>? In the diagram it is initialized to 0. It seems like phase estimation but there is an H missing before measurement. Also what the measurement results in 0 you mean on the state |0> 100% of the times? Jun 14 at 7:34
• You should also provide the source to your example. Jun 14 at 7:35