A search for water masers in the gravitationally lensed quasars H1413+117 and MG 0414+0534

We searched for 22 GHz water maser emission from two gravitationally lensed quasars, H1413+/-117 (the Cloverleaf) at z = 2.56 and MG 0414+0534 at z = 2.64, using the Australia Telescope Compact Array. Detections of CO emissio n at millimeter wavelengths from these systems provide the redshifts of the molecular components with high precision and suggest substantial reservoir s of molecular gas. The observations were made with similar to 750 km s(-1) of velocity coverage, enough to span the entire range of CO emission. No n arrow water maser features were found in the observed bands in either sourc e, though the sensitivities achieved were sufficient for detection if eithe r (1) the water maser luminosity were substantially larger than found in ne arby low-power active galactic nuclei (AGNs), which maser theory suggests i s plausible, or (2) the water maser luminosity were typical of nearby detec ted AGNs but magnified by an extremely large factor, as might be the case n ear a lens caustic. The detection limits for a 1.5 km s(-1) channel corresp ond to isotropic maser luminosities of a few 1000(m/10)(-1) L., where m is the lensing magnification factor, values that are comparable to the most lu minous AGN water masers in the local universe for m approximate to 10.