INTERPRETING THE LIGHT-CURVE OF Q2237 + 0305

Theoretical modeling of the mass distribution in the lens for Q2237 + 0305 will not give an accurate estimate of the microlensing parameters for each of the images. It will be possible to statistically estimate microlensing parameters from the data, however the timescales over which data must be collected, may be uncomfortably long. The required timescale depends on both the mean compact object mass and the apparent transverse velocity of the source, and is greater-than-or-similar-to 130(m/M.)0.5 (5000 km s-1/upsilon(t)) years. The observation of the quasar continuum source crossing a caustic or cusp line gives a good estimate of the source size. Our best estimate from the current data is less-than-or-similar-to 4 X 10(-4) (upsilon(t)/5000 km s-1)pc. General characteristics of the light curves will tell us about the nature of cluster and halo dark matter. Preliminary indications, principally from the lensed quasar 0957 + 561, suggest that cluster dark matter comprises objects smaller than approximately 0.1 M.. A better understanding of the mass distribution in the principle lensing galaxy for these two gravitationally lensed quasars and careful monitoring of the individual images on a regular basis (weekly for Q2237 + 0305) would provide the required statistical base to better determine the quasar source size, the nature of dark matter, and the masses of compact objects responsible for microlensing.