PART ONE
Robert Rucker has used the remarkable computing power of Monte Carlo N-Particle software to calculate the enrichment of radiocarbon that would ensue in a shroud, given a simple model man-in-a-tomb, a uniform generation of neutrons within the man, and just enough to produce a radiocarbon date 1400 years ahead of the cloth’s actual date in an area of the shroud close to the man’s feet. 1
If the Shroud of Turin is actually 1400 years older that the radiocarbon dating of 1988 indicated, then the emission of neutrons in the manner described could account for it. However there is no evidence that any such emission occurred, and consequently this model is no evidence that the radiocarbon dating was wrong. But read on…
This is Bob Rucker’s model.
Neutrons emitted from the bottom or far side of the body can affect the carbon of the shroud as they emerge, and then again after they reflect off the shelf or wall of the tomb, so those parts of the Shroud will be more enriched than the rest. If the shroud be divided into rectangles, the average apparent age of each one can be calculated. Here are the values for the shroud, approximately overlaid by a photo of the Shroud, to give an idea of position.
They are not easy to read, and mostly represent ages far into the future. Their distribution can best be appreciated by graphing each row. The solid black lines represent the year 2000 AD.
These are the radiocarbon profiles along the length of the shroud. Representative profiles across the width (each graph from the wall side on the left to the open side on the right) look like this:
It is clear that there is much greater distinction between the dorsal and ventral images than there is between the wall-side and the open-side of the cloth, corresponding to the right-hand side and the left hand side of the man.
PART TWO
Enter Tom McAvoy, who was interested in the ultra-violet fluorescence photographs of Vernon Miller and Sam Pellicori, whose work for STuRP was written up in the Journal of Biological Photography in 1981. 2 Seven of their photos were published in the paper, shown below against a background of the Shroud.
It is immediately apparent that these photos were either not all photographed under the same conditions, or that subsequent processing, manipulation and/or printing was not uniform. The 1st, 2nd, 5th and 7th look similar to me, in terms of their slightly reddish tinge, the others all look significantly less so.
In fact Miller and Pellicori took 23 photos, in three long strips from left to right, which took some while to become available to researchers. The outside strips are shown below.
In general, the upper row seem different from the lower, with the 3rd one along particularly odd.
McAvoy wondered if the overall fluorescence of the Shroud really did vary from place to place, and subjected the photos to considerable manipulation to try to present them all as if they had been taken and printed under identical conditions.3 Any variations in them would then be due to variations on the cloth. He also obviated the more obvious actual variations, such as the burn patches. Here is his reconstruction, split into three strips so that the middle one doesn’t overlap the outer ones. Irreconcilable anomalies have apparently been omitted.
Further analysis has enabled McAvoy to derive what he thinks are consistent fluorescence intensities, and therefore a general picture of the variation of fluorescence intensity all over the Shroud. The graph below is redrawn from his data.
PART THREE
In subsidiary tests, McAvoy confirmed that irradiating linen with neutrons make it fluoresce. The question is, does the UV fluorescence of the Shroud match the MCNP data calculated by Rucker? If it does, then it is powerful evidence that the Shroud has been irradiated with neutrons.
Here then, is Rucker’s and McAvoy’s data superimposed. Since Rucker’s data is in five strips along the Shroud, and McAvoy’s only three, the outer MCNP values have been approximately adjusted to take this into account, by taking the averages of Rucker’s two outside upper strips, and two outside lower strips. The y-axis is arbitrary, and for the fluorescence data, has been adjusted to make them fit as well as they can.
In spite of an encouraging closeness of the match in the second of these diagrams, I cannot agree with McAvoy’s conclusion, “The shape of the Shroud’s average UV fluorescence intensity spatial variations very closely matches the shape of the spatial radiocarbon dating variations calculated by Rucker in his computer simulation of Phillips’ neutron hypothesis.” On the contrary, it is clear that overall there is no correlation between the fluorescence of the Shroud as discovered by Tom McAvoy and the putative neutron enrichment suggested by Bob Rucker.
1 Rucker, Robert, ‘The Carbon Dating Problem for the Shroud of Turin, Part 3: The Neutron Absorption Hypothesis,’ 2018, at academia.edu
2 Miller, Vernon and Pellicori, Sam, ‘Ultraviolet Fluorescence Photography of the Shroud of Turin,’ Journal of Biological Photography, 1981, at shroud.com
3 McAvoy, Thomas, ‘Analysis of UV Photographs of the Shroud of Turin,’ Applied Optics, 2019
McAvoy, Thomas, ‘Shroud of Turin Ultraviolet Light Images: Color and Information Content,’ Applied Optics, 2021
McAvoy, Thomas, ‘On Radiocarbon Dating of the Shroud of Turin,’ International Journal of Archaeology, 2021