This letter proposes an analog active noise control (ANC) circuit with an all-pass filter (APF). To improve performance of the previously reported analog ANC circuit, we inserted an APF to the circuit in order to fit phases of a noise and an electrical signal in the circuit. As a result, we confirmed improvement of the noise canceling effect of the analog ANC circuit.

We propose to study in-medium mass modification of the phi meson using the formation of phi meson bound state. We demonstrate that a clear missing-mass spectrum can be obtained efficiently by ((p) over bar, phi) spectroscopy together with the A tagging, using the primary reaction channel (p) over barp -> phi phi. A systematic study over several nuclear targets will yield a unique, definitive and precise determination of the in-medium mass modification of the vector meson phi(s (s) over bar)