Metal Vapor Flux Characterization from a Single Channel of a Multi-Channel Source

摘要

Generation of metal atomic vapor is a prerequisite to study multi-step photoionized laser produced plasma. We have developed a radiatively heated furnace with collinear channel sources, which has been used to generate a strip-type effusive atomic beam of barium in the vertical direction. By shining lasers at a certain height from the source photoplasma is generated and studied. To charactefize the barium vapor flux in the laser-atom interaction region we have used deposition technique. Arrangement has been made to select the central channel from the multi-channel collimator and deposition experiments are carried on it. Barium vapor is allowed to deposit on metal foil for a known time at a particular temperature. A movable shutter below it controls the exposure time. The deposited barium is dissolved in nitric acid and total amount of barium is analyzed by Directly Coupled Plasma-Atomic Emission Spectrometry (DCP-AES) technique. Using appropriate analytical expressions for effusive source, atom vapor flux is estimated. A comparison with experimental results showed good agreement. The details of the experiments, their results and interpretation will be discussed in this paper.