A GRAVITATIONAL LENS MODEL FOR THE Lyα EMITTER LAE 221724+001716 AT z = 3.1 IN THE SSA 22 FIELD

During the course of our Lyman continuum imaging survey, we found that the spectroscopically confirmed Ly alpha emitter LAE 221724+001716 at z = 3.10 in the SSA 22 field shows strong Lyman continuum emission ([lambda] sub(rest) ~ 900 [Angstrom]) that escapes from this galaxy. However, another recent spectroscopic survey revealed that the supposed Lyman continuum emission could arise from a foreground galaxy at z = 1.76 if the emission line newly detected from the galaxy at [lambda] sub(obs) [asymptotically =] 3360 [Angstrom] is Ly alpha . If this is the case, as the angular separation between these two galaxies is very small ([asymptotically =]0".6), LAE 221724+001716 at z = 3.10 could be amplified by the gravitational lensing caused by this intervening galaxy. Here we present a possible gravitational lens model for the system of LAE 221724+001716. First, we estimate the stellar mass of the intervening galaxy as M[low *] ~ 3.5 x 10 super(9) M sub([middot in circle]) from its UV luminosity and ~3.0 x 10 super(7)-2.4 x 10 super(9) M sub([middot in circle]) through the spectral energy distribution fitting. Then, we find that the gravitational magnification factor ranges from 1.01 to 1.16 using the so-called singular isothermal sphere model for strong lensing. While LAE 221724+001716 is the first system of an LAE-LAE lensing reported so far, the estimated magnification factor is not so significant because the stellar mass of the intervening galaxy is small.