| 摘要 |
<p>An atomic beam tube provides a single sealed envelope structure that serves both as vacuum envelope and as structural member to which the operative components are attached. The envelope is composed of a heavy and relatively rigid frame and a relatively thin and flexible coves sealed to the frame. The operative elements are separately assembled in independent subassembly units which are secured to the frame as a minimum of locations to provide fixed alignment and thermal isolation of the operative elements, and easy disassembly of the tube. C-field means in the improved molecular beam tube-apparatus for producing a weak magnetic field comprise a conductor including a plurality of equally spaced helical turns forming a generally closed loop lying generally in a beam plate including the path of the beam. The loop including two end sections transverse to the beam path and parallel to one another, each of the end sections including a beam aperture having first and second opposed edges interrupting the conductor in at least two adjacent helical turns to provide two internal ends adjacent each of the opposed beam aperture edges. There are at least two conducting jumpers adjacent a beau aperture, each said jumper having a first jumper end connected to the helical turn internal end adjacent the first aperture edge, and a second jumper end connected to the internal end of the same helical turn adjacent the opposed second edge, whereby the conductor provides a continuous conducting path through the helical turns and the jumpers around said beam apertures, and the magnetic field adjacent an aperture has greater strength than at other portions of the loop.</p> |
