A Gravitational Lens Model for the Lya 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 Lya emitter LAE 221724+001716 at z = 3.10 in the
SSA 22 field shows strong Lyman continuum emission (lambda_rest ~ 900 A) 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_obs ~
3360 A is Lya. If this is the case, as the angular separation between these two
galaxies is very small (~ 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
Mstar ~ 3.5x10^9 Msun from its UV luminosity and ~ 3.0x10^7--2.4x10^9 Msun
through the SED 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.
