Vacuum furnaces have been widely used to generate atomic beams of metals. By shining lasers on atomic beams photoplasma is produced and are studied. We have developed a double furnace system to be operated in high vacuum to generate and study barium atomic beam and photoplasma. Of the two furnaces one which is housed in the lower half of the experimental chamber is essentially used to generate a strip-type effusive beam moving vertically upwards. The atom density characterization of the beam is discussed in another paper in this symposium. The other furnace located above the lower furnace and in a region where laser-atom interact is used to study the photoplasma in the background of dense metal vapor. Two parallel plate electrodes bound the laser-atom interaction region located in the upper part of the experimental chamber symmetrically. The top furnace is so designed that it heats the electrodes which are located in the interaction region. The heating element is a rectangular structure with tantalum wire wound over alumina on four sides leaving the bottom and top open for the passage of atoms. This structure encloses the electrodes. Two electrically insulating plates and several thermal heat shields, having open slots for the atoms to pass through, separate it from the bottom furnace. Similar plates and shields also enclose the sides and top. We have calibrated the furnace for temperature and have measured its heating and cooling as a function of time. Details of the furnace and experiments will be discussed in this paper.
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