LIBS; Variation; Experimental design; Normalization; Statistics;INDUCED BREAKDOWN SPECTROSCOPY; FLOAT GLASS; SPECTROMETRY; DISCRIMINATION

Laser Induced Breakdown Spectroscopy (LIBS) is an analytical chemistry technique that has the potential to identify and measure the elements in a substance of interest. LIBS is applicable for any phase (solid, liquid or gas). LIBS has gained importance in the fields of material identification, biomedical science, forensics, military, art and archaeology in the recent years. In spite of its many advantages over other instruments, it has a few drawbacks such as poor precision and repeatability. That is, different spectra may be observed for the same sample over successive runs. This indicates poor precision of the instrument. This paper presents an experiment designed to investigate the claim that there is higher variation in the experiments conducted on different days as compared to the experiments conducted on the same day. This study examines the variability in the spectra between the runs on the same day, and the variability between runs on different days using samples from a standard reference glass, and discusses the conclusions that can be drawn from the results. (C) 2017 Elsevier B.V. All rights reserved.