If the Hoyle state energy was at 479 keV or more above the three alpha particles
, then the amount of carbon produced would be too low for carbon-based life," Lee said.
While at ORNL and then as Theory Head at the PSFC he pursued his interest in the role of alpha particles
in burning tokamak plasmas.
Liment Ohridski University of Sofia, Bulgaria, and his colleagues investigated the capability of alpha particles
to mark plastic as they collide with it.
can be stopped by a piece of paper or skin.
Finally, the role of alpha particles
in turbulence and transport, which will be an important issue for burning plasmas, is not well understood.
Thus an alpha particle
(a helium nucleus) had four times the mass of a proton but a positive charge only twice that of a proton.
When the researchers irradiated all the nuclei with exactly one alpha particle
each, 98 mutations of a certain gene occurred per 100,000 surviving cells.
Throughout its short trip, however, each alpha particle
releases a wallop of energy, giving the kiss of death to any cells it crosses.
Ramayya and his coworkers have also found that californium-252 sometimes breaks into three fragments--two of moderate size and one as small as a helium nucleus (or alpha particle
In the process of the bombardment, the nucleus of the aluminum atom would absorb an alpha particle
and give off a proton.
"The beauty of the alpha particle
," he observes, "is that it travels only about 50 microns--which is approximately three to five cell diameters." Though his initial trial is designed to identify maximum tolerable doses for treatment, not to assess efficacy, "we've already seen significant antileukemic activity in the patients we've treated," he told Science News.
In 1940 Segre, who had isolated technetium (see 1937), bombarded bismuth (element number 83) with alpha particles
. If an alpha particle
struck the bismuth and remained, or even if a neutron were emitted thereafter, the bismuth would have gained two protons and the result would be the undiscovered element number 85.