B1951+32 pulsar bow shock proper motion measurements based on Gemini North 8-m telescope and HST optical observations

Using deep optical images of the core of the CTB 80 supernova remnant, obtained with 8-m Gemini-North telescope in 2016, and archival HST images of 1997, we measured the proper motion shift of a bright [OIII] structure ahead of the fast moving pulsar B1951+32 associated with the remnant. An arc shape of the structure suggests that it is a bow shock created by the supersonic motion of the pulsar in the ambient matter, while no direct evidence of that have been presented. The measured arc shift of ≈ 0.53″ is compatible with the pulsar proper motion shift of ≈ 0.6″ based on the radio interferometry measurements. This strongly supports the bow-shock nature of the structure.