
Nuclear technology with gamma rays to protect artistic heritage
Nuclear technology is an important tool when it comes to their restoration and discovering their secret, as well as to delve deeper into the research of objects of archeological interest. Nuclear technology helps to collect information on their age, composition and geographic origins, as well as to diagnose problems. There are special radiation techniques to disinfect and clean damaged pieces.
The International Atomic Energy Agency (IAEA) cooperates with various laboratories in its member states to develop and apply these techniques via national and regional cooperation programmes. According to the Agency, the advantage of these techniques is that they may be applied to a wide variety of materials and the analysis can be done in a non-destructive way or with a minimum invasion of the sample.
The X-ray fluorescence technique (XRF) is used to analyze the chemical composition of objects
The X-ray luorescence technique (XRF) is used to analyze the chemical composition of objects. It consists of "bombarding"a sample with X rays to destabilize the electron structure and push them to emit radiation. Since the radiation is different in each chemical element, the chemical elements in the sample can be determined. This technique has been used, for instance, to identify the pigments used in the paintings of Leonardo Da Vinci. Thanks to XRF it was discovered that, besides lapis lazuli, there were also other colors made with cobalt that were not used until some time after the artist's time, which indicates that the painting was retouched later on. The different layers applied can also be detected.
At the Art History Museum in Vienna, The XFR technique was used on Indonesian Kris daggers to detect traces of minerals from a meteorite that fell in the area in the 18th century. The method also has the advantage that it can be applied with a small gun-shaped device. This makes it easy to transport, which is very important in the case of artwork that cannot be moved for security reasons, such as wall frescoes or large sculptures.
Another important nuclear application in art are ionizing radiations to disinfect and clean artworks and historical objects affected by different types of parasites
Another important nuclear application in art are ionizing radiations to disinfect and clean artworks and historical objects affected by different types of parasites. It's important to remember that the materials treated with ionizing radiations do not become radioactive, nor are they damaged. The technique consists in transferring energy to the microorganisms that reside inthe object, altering their DNA without affecting the rest. There are two different dose levels: a lower one for insects (their DNA is more complex and susceptible to radiation damage) and a higher one for mold.
This technique was first applied in 1977 to disinfect the mummy of Ramesses II. Since then it is used in the field of cultural heritage. In 2010 it was used to neutralize the germs that were affecting the soft tissues in Khoma, a 50,000 year old mammoth that was found frozen in the Siberian permafrost.