Evaluation of bubble breakdown limit in LHe below 4.2 K

An antibubble barrier model which may explain the high breakdown strength of saturated LHe at very low temperatures is presented. The occurrence of the barrier is an intrinsic liquid phenomenon. Up to a threshold field of 40 MV/m, the barrier seems the sole effective obstacle against breakdown. However, adverse extrinsic effects which may prevail under engineering conditions can favor surmounting of the antibubble barrier. Liquid breakdown at lower field stress may therefore be possible in applications.>