Galaxy-scale lens search in the PEARLS NEP TDF and CEERS JWST fields

We present four galaxy scale lenses discovered in two James Webb Space Telescope (JWST) blank-fields: the ~54 arcmin² of the PEARLS North-Ecliptic-Pole Time-Domain Field (NEP TDF) and in the ~90 arcmin² of CEERS. We perform the search by visual inspection of NIRCam photometric data, obtaining an initial list of 16 lens candidates. We down-select this list to five high-confidence lens candidates, based on lens modelling of the image configuration and photometric redshift measurements for both the source and the deflector. We compare our results to samples of lenses obtained in ground-based and space-based lens searches and theoretical expectations. We expect that JWST observations of field galaxies will yield approximately one galaxy scale lens every three to four NIRCam pointings of comparable depth to these observations (~9 arcmin² each). This shows that JWST, compared to other lens searches, can yield an extremely high number of secure lenses per unit area, with redshift and size distributions complementary to lens samples obtained from ground-based and wide-area surveys. We estimate that a single JWST pure-parallel survey of comparable depth could yield ~80 galaxy scale lenses, with a third of them having z_lens > 1 and z_source > 3.