True muonium resonant production at e + e − colliders with standard crossing angle

True muonium (TM) (mu (+) mu (-)) is the heaviest and smallest bound state not containing hadrons, after TM (tau (+ )tau( -)) and mu-tauonium (mu( +/-) tau (sic)). One of the proposed methods to observe the spin 1 fundamental state of TM, which has the smallest lifetime among TM spin 1 states, was to build an e (+) e( -) collider with a large crossing angle (theta similar to 30(degrees)) in order to provide TM with a large boost and detect its decay vertex in e + e -. The following paper will instead show that TM excited states can be observed in relatively large quantities ( O (10)/month) at a e (+) e (-) collider with standard crossing angle, after setting their center-of-mass energy to the TM mass (similar to 2m mu = 211.4 MeV).