Dubnium has been synthesized only a few times in its brief history. The complicated methods that are needed to produce dubnium, and the short half life of dubnium isotopes, have hindered scientific studies of this element. The first time that dubnium was synthesized was in 1967. At this time, researchers used americium and neon isotopes. The process involved bombarding the americium with neon to produce two isotopes of dubnium: isotope number 260 and isotope number 261. The second synthesis of dubnium occurred in 1970. At this time, researchers used nitrogen and californium. During this procedure, a target composed of californium was hit with a beam of nitrogen nuclei, (84 MeV), in a particle accelerator. An isotope of dubnium was produced, number 260, which had a half life of only 1.6 seconds. Dubnium is a radioactive element, but to what extent is not known. Further studies of the element are planned, but at this time no additional research has been conducted.