Reactor sampling apparatus, system, and method

A probe tube subassembly for a sampling apparatus, said probe tube subassembly comprising:

• a probe tube;
• A retaining sleeve connected to a distal end of the probe tube;
• an inner sleeve positioned within the retaining sleeve and comprising apertures;
• sample tubes, each extending in an at least substantially straight line, including through the probe tube and into a respective one of the apertures;
• and
• a sample head positioned within the inner sleeve and comprising a pocket located at a distal end portion thereof, wherein the sample head is axially slidable within the inner sleeve and relative to the sample tubes between an extended position where the pocket is exposed from the inner sleeve to an ambient environment, and a retracted position where the pocket is covered by the inner sleeve;
• wherein a distal end of each of the sample tubes extends from the distal end of the probe tube and terminates adjacent to the pocket of the sample head when the sample head is in the retracted position.