Low temperature air plasma jet generated by syringe needle–ring electrodes dielectric barrier discharge at atmospheric pressure

•Air plasma jet was generated by the dielectric barrier discharge.•Plasma jet length reached about 25 mm.•Gas temperature was close to the room temperature.•Active species (O*, N2*, N2+, and N*) were detected in the plasma plume.

A low temperature air plasma jet was generated by syringe needle–ring electrodes dielectric barrier discharge at atmospheric pressure. It was found that the air plasma jet length reached about 25 mm and the gas temperature was close to the room temperature. Besides, the optical emission spectrum showed that a large number of active species, such as O* (777.2 nm), O* (794.7 nm), O* (799.5 nm), O* (844.6 nm), N2* (C-B), N2* (B-A), N2+ (B-X), N* (750.7 nm), N* (812.9 nm), etc., existed in the air plasma plume.