We investigate the possibility of detecting H I emission from gravitationally lensed H I clouds (akin to damped Lyα clouds) at high redshift by carrying out deep radio observations in the fields of known cluster lenses. These observations will be possible with current radio telescopes only if their lenses substantially magnify the flux of the H I emission. While at present this holds the only possibility of detecting the H I emission from such clouds, it has the disadvantage of being restricted to clouds that lie very close to the caustics of the lens. We find that observations at a detection threshold of 50 μJy at 320 MHz (possible with the Giant Meterwave Radio Telescope) have a greater than 20% probability of detecting an H I cloud in the field of a cluster, provided the clouds have H I masses in the range 5 × 108 M☉ M 2.5 × 1010 M☉. The probability of detecting a cloud increases if it has larger H I masses except in cases where the number of H I clouds in the cluster field is very small. The probability of detection at 610 and 233 MHz is comparable to that at 320 MHz, although a definitive statement is difficult owing to uncertainties in the H I content at the redshifts corresponding to these frequencies. Observations at a detection threshold of 2 μJy (possible in the future with the Square Kilometer Array) are expected to detect a few H I clouds in the field of every cluster, provided the clouds have H I masses in the range 2 × 107 M☉ M 109 M☉. Even if such observations do not result in the detection of H I clouds, they will be able to put useful constraints on the H I content of the clouds.
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