The tank has been emptied of liquid Nitrogen. We will remove the
insulation and view the crack from the inside. We believe we have a
good model of why the crack developed. Briefly, the tank leg was
damaged in the past, before we took possession. When we loaded the
inner tank with liquid Nitrogen, the weight when transmitted to the
outer tank structure caused excess stress to the damaged region,
which caused the crack to spread. There may have been a very small
crack all along. It will be at least two weeks until we can repair
the crack, test it, and be ready to cool-down again. Therefore, we
will put four detectors into the ring and prepare for the penultimate
flash test which should occur before we power the ring. A simulated
inflector channel is being made. For the CERN experiment, the maximum
flash was associated with pions hitting the inflector channel (I have
the CERN logbooks in my office: see page 114 of Logbook 1).