We suggest a few particle physics processes in which excited 2p pionium A(2 pi)' may be observed. They include the e(+)e(-) -> pi(+)pi(-) annihilation, the V-0 -> pi(0)l(+)l(-) and K-+/- -> pi(+/-)l(+)l(-) (l = e, mu) decays, and the photoproduction of two neutral pions from nucleons. We analyze available experimental data and find that they, in some cases, indicate the presence of 2p pionium, but do not provide definite proof.