Response to “Comment on ‘Invalidation of the Intracavity Optogalvanic Method for Radiocarbon Detection’” by Daniel E Murnick

Abstract

ABSTRACT. Our results, when taken alongside those of two other research groups, appear to invalidate the early positive results for intracavity optogalvanic spectroscopy (ICOGS) and its detection of radiocarbon. Daniel Murnick, whose lab published those early results, has directed a comment setting out the perceived shortcomings of our article and the reasons that the results do not constitute invalidation, as our article claims. Absent support from his own findings or published literature, his various counterclaims regarding our experimental procedure appear to constitute only his considered professional opinion and the largest confounder highlighted by our research is not even mentioned. The preponderance of documented evidence regarding ICOGS clearly supports the null hypothesis and in our opinion, nothing in Murnick's comment indicates otherwise. RESPONSEDaniel Murnick has submitted a comment in defense of his earlier publications regarding the detection of radiocarbon with intracavity optogalvanic spectroscopy (ICOGS), in which he points out perceived shortcomings in our research (Carson et al. 2016). Whereas we would expect insightful criticism from such an eminent scholar in the field, we were instead dismayed to read weak and unsubstantiated counterclaims to our findings.His first criticism is that we should have demonstrated unequivocally that his earlier results could not be reproduced under identical conditions. We felt that this had already been accomplished in two different laboratories, at Groningen University and at Uppsala University (Persson et al. 2013;Paul and Meijer 2015;Persson and Salehpour 2015), but he arbitrarily disregards their findings. For what reason should we also disregard the invalidating results from other laboratories when no evidence is produced to discredit them? Second, he claims that the theoretical basis for our findings was invalid. Our theoretical basis is an extension of the model he espoused in his own peer-reviewed publications. Compare what we present against his own model ( Murnick et al. 2008). We expanded one of his products into an integral and placed rough bounds on his own otherwise unspecified term K, which "is a corresponding optogalvanic proportionality constant that depends on the details of the electric discharge" (Murnick et al. 2008). If our model is invalid because of the reasonable caveats of Bachor et al. (1982), should this not also challenge his own published model? Third, he claims that the crucial flaw in our experiment was that we used sawtooth modulation, "[making] the intrinsically narrow band CO 2 laser effectively broadband." Rather than provide evidence drawn from a comparable CO 2 laser operated in a similar fashion, the support is claimed from an entirely different system (Genoud et al. 2015). The "lower sensitivity" found by Genoud et al. compared to Galli et al. (2013) was attributed by Munick to the line scanning, not to any of the other potential sources of discrepancy. Genoud et al. was working at~275 K at 20 mbar with a 3-mW quantum ...