We report on the first deep optical observations of two \gamma -ray pulsars , both among the very first discovered by the Fermi Gamma-ray Space Telescope .
The two pulsars are the radio-loud PSR J1907+0602 in the TeV pulsar wind nebula ( PWN ) MGRO J1908+06 and the radio-quiet PSR J1809 - 2332 in the ” Taz ” radio/X-ray PWN .
These pulsars are relatively young and energetic and have been both detected in the X-rays by XMM-Newton , which makes them viable targets for optical observations .
We observed the pulsar fields in the B and V bands with the Very Large Telescope ( VLT ) in June/July 2015 to search for their optical counterparts .
Neither of the two pulsars has been detected down to 3 \sigma limiting magnitudes of m _ { v } \sim 26.9 and m _ { v } \sim 27.6 for PSR J1907+0602 and PSR J1809 - 2332 , respectively .
We discuss these results in the framework of the multi-wavelength emission properties of pulsars .