Direct production of χ c 1 at BESIII

The production of resonances in electron-positron annihilation has only been observed for states with quantum numbers J PC = 1 −− , while C = +1 resonances appear only among the decay products. The direct production of the 1 ++ states could happen through two-photon or neutral current. Due to the smallness of the production rate, this process has never been verified experimentally. With the high luminosity and good performance of the BESIII experiment, a search of the direct production of the 1 ++ state in charmonium region, χ c 1 , is undergoing with dedicated data samples around the χ c 1 mass. An overview of the data analysis will be presented.