An atomic particle detection assembly includes at least one atomic particle detector positioned within a first chamber having a first operating pressure. The assembly also includes at least one junction apparatus coupled to the at least one atomic particle detector. The at least one junction apparatus includes at least one wall that at least partially defines a second chamber having a second operating pressure. The second pressure is greater than the first pressure and the at least one junction apparatus facilitates maintaining a predetermined pressure difference between the first chamber and the second chamber.